# Menu 3 − Speed Control and Position Feedback

Mode: RFC‑S

Normally the units for speed parameters are rpm for both rotary and linear applications. For a linear application one revolution corresponds to one motor pole. If the position feedback device that is selected for motor control with Motor Control Feedback Select (03.026) is a linear device then if Linear Speed Select (01.055) is set to 1 the units for speed parameters are mm/s with the following exceptions:

1. All speed parameters are displayed in rpm if sensorless mode is active, i.e. Sensorless Mode Active (03.078) = 1.
2. Speed feedback parameters associated with each feedback interface, i.e. P1 Speed Feedback (03.027) for position feedback interface P1, etc., are always displayed in rpm for a rotary device.

Position feedback interfaces

Two position feedback interfaces with associated freeze system are provided. Access to both these interfaces and the encoder simulation output are provided via one 15 way high density connector. There are limitations on the functions that can be provided simultaneously as shown in the table below along with the connections required for each combination of functions.

Functions | Connections
P1 Position feedback interface | P2 Position feedback interface | Encoder Simulation Output | 1/2 | 3/4 | 5/6 | 7/8 | 9/10 | 11/12 | 13/14 | 15
AB Servo, FD Servo, FR Servo |  |  | A1 | B1 | Z1 | U1 | V1 | W1 | PS1 | Th
SC Servo |  |  | Cos1 | Sin1 | Z1 | U1 | V1 | W1 | PS1 | Th
AB, FD, FR | AB, FD, FR |  | A1 | B1 | Z1 | A2 | B2 | Z2 | PS1 | Th
AB, FD, FR | EnDat, BiSS, SSI |  | A1 | B1 | Z1 | D2 | Clk2 | Z2 | PS1 | Th
AB, FD, FR |  | Full | A1 | B1 | Z1 | AOut | BOut | ZOut | PS1 | Th
SC | AB, FD, FR |  | Cos1 | Sin1 | Z1 | A2 | B2 | Z2 | PS1 | Th
SC | EnDat, BiSS, SSI |  | Cos1 | Sin1 | Z1 | D2 | Clk2 | Z2 | PS1 | Th
SC |  | Full | Cos1 | Sin1 | Z1 | AOut | BOut | ZOut | PS1 | Th
Resolver | AB, FD, FR |  | Cos1 | Sin1 | Ref1 | A2 | B2 | Z2 | PS1 | Th
Resolver | EnDat, BiSS, SSI |  | Cos1 | Sin1 | Ref1 | D2 | Clk2 | Z2 | PS1 | Th
Resolver |  | Full | Cos1 | Sin1 | Ref1 | AOut | BOut | ZOut | PS1 | Th
SC Hiperface | AB, FD, FR |  | Cos1 | Sin1 | D1 | A2 | B2 | Z2 | PS1 | Th
SC Hiperface | EnDat, BiSS, SSI |  | Cos1 | Sin1 | D1 | D2 | Clk2 | Z2 | PS1 | Th
SC Hiperface |  | Full | Cos1 | Sin1 | D1 | AOut | BOut | ZOut | PS1 | Th
SC EnDat, SC SSI, SC BiSS | AB, FD, FR No Z marker pulse |  | Cos1 | Sin1 | D1 | A2 | B2 | Clk1 | PS1 | Th
SC EnDat, SC SSI, SC BiSS | EnDat, BiSS, SSI |  | Cos1 | Sin1 | D1 | D2 | Clk2 | Clk1 | PS1 | Th
SC EnDat, SC SSI, SC BiSS |  | No Z marker pulse | Cos1 | Sin1 | D1 | AOut | BOut | Clk1 | PS1 | Th
EnDat, BiSS, SSI | AB, FD, FR |  | D1 | Clk1 | Z1 | A2 | B2 | Z2 | PS1 | Th
EnDat, BiSS, SSI | EnDat, BiSS, SSI |  | D1 | Clk1 | Z1 | D2 | Clk2 | Z2 | PS1 | Th
EnDat, BiSS, SSI |  | Full | D1 | Clk1 | Z1 | AOut | BOut | ZOut | PS1 | Th
EnDat, BiSS, SSI | EnDat, BiSS, SSI | No Z marker pulse | D1 | Clk1 | D2 | AOut | BOut | Clk2 | PS1 | Th
SC SC |  |  | Cos1 | Sin1 | Z1 | SCs1 | SSn1 | Z2 | PS1 | Th
Commutation Only |  |  |  |  |  | U1 | V1 | W1 | PS1 | Th
EnDat Alt, SSI Alt, BiSS Alt | AB, FD, FR No Z marker pulse |  | * | * | D1 | A2 | B2 | Clk1 | PS1 | Th
EnDat Alt, SSI Alt, BiSS Alt | EnDat, BiSS, SSI |  | * | * | D1 | D2 | Clk2 | Clk1 | PS1 | Th
EnDat Alt, SSI Alt, BiSS Alt |  | No Z marker pulse | * | * | D1 | AOut | BOut | Clk1 | PS1 | Th
EnDat 3 | AB, FD, FR |  | D1** | ** | D1** | A2 | B2 | Z2 | PS1 | Th
EnDat 3 | EnDat, BiSS, SSI |  | D1** | ** | D1** | D2 | Clk2 | Z2 | PS1 | Th
EnDat 3 |  | Full | D1** | ** | D1** | AOut | BOut | ZOut | PS1 | Th

*These inputs are unused. If an SC EnDat, SC SSI or SC BiSS encoder is connected to the P1 interface the sine wave signals from the device will be connected to these inputs. If EnDat Alt, SSI Alt or BiSS Alt are selected then the position feedback can be derived from the encoder communications alone and the sine wave signals will be ignored by the drive.

**EnDat 3 uses connections 1/2 and 5/6 for receiving and transmitting on the drive respectively, therefore both of these need to be connected to the encoder data lines. For 2-wire EnDat 3 encoders, these connections are made on an external 2-wire interface board. This board also combines the communication signals with the power supply for the encoder and provides the termination resistors. Connections 3/4 are not used by EnDat 3 but cannot be used on their own for any other operation so are always unused.

The marker inputs can be used without their associated position feedback as freeze trigger inputs, therefore these are present where possible even if the associated incremental or SINCOS position feedback is not possible. The table below gives the connection functions associated with the codes used.

Connection Function | Connection Definition
Position Interface inputs
A | A input for AB, or AB Servo encoders F input for FD, FD Servo, FR or FR Servo encoders
B | B input for AB, or AB Servo encoders D input for FD or FD Servo encoders R input for FR or FR Servo encoders
Z | Z input for AB, AB Servo, FD, FD Servo, FR, FR Servo, SC encoders Freeze input
U, V, W | Commutation signals for AB Servo, FD Servo, FR Servo, SC Servo or Commutation Only encoders
Cos, Sin | Cosine and Sine inputs for SC, SC EnDat, SC Hiperface, SC SSI or SC Servo encoders Cosine and Sine inputs for resolvers
Ref | Reference output for resolvers
D | Data input/output for SC EnDat, SC Hiperface, SC BiSS, EnDat, EnDat 3 or BiSS encoders Data input for SC SSI, SSI encoders
Clk | Clock output for SC EnDat, SC BiSS, SC SSI, EnDat, BiSS or SSI encoders
SCs, SSn | Single turn Cosine and Sine signals used to determine the absolute position within one turn
Encoder Simulation Output
AOut | A output for AB or AB Lock modes F output for FD, FD Lock or FR modes Data output for SSI Gray or SSI Binary modes
BOut | B output for AB or AB Lock modes D output for FD, FD Lock or FR modes Clock input for SSI Gray or SSI Binary modes
Zout | Z output for AB, AB Lock, FD, FD Lock or FR modes
Power Supply and Temperature Measurement
PS1 | Power supply output (13 = Supply, 14 = 0V)
Th | Temperature measurement input

Position and speed measurement timing

The position information is taken at each current control datum point which is at the start of each current controller task (shown as "I" in the diagram below). The current controller sample period varies with switching frequency. At each of these datum points the position of the motor within one revolution is required for basic motor control. The speed controller sample period is 250us for all switching frequencies, and so the speed control datum points (shown as "S" in the diagram below) occur every 250us. At each of these datum points the full encoder position is obtained and all calculations related to this are completed. The diagram below shows examples of the datum points for switching frequencies of 12kHz and 16kHz. The internal "I" datum points are not visible outside the drive control system. The "S" datum points are used to synchronise with option modules.

P1 Position feedback interface

P2 Position feedback interface

The P2 position feedback interface duplicates most of the parameter structure and functions of the P1 feedback interface. The P2 interface parameters (03.127 to 03.169) have the same functions as the P1 interface parameters (03.027 to 03.069) except that parameters 03.136, 03.139, 03.162 and 03.163 are not included because the P2 interface does not have its own position feedback power supply, does not support resolvers, and the termination resistors are not selectable and are always enabled. Also P2 Device type (03.138) has less possible settings because the P2 interface does not support all the devices supported by the P1 interface.

Priority of the 15-way D-type is assigned in the following order from the highest priority to the lowest.

1. P1 position interface
2. Encoder simulation output
3. P2 position interface

The availability of the P2 position interface on the 15-way D-type on the drive is dependent on type of feedback device selected in P1 Device Type (03.038) and the encoder simulation mode selected in Encoder Simulation Mode (03.088). P2 Status (03.172) shows the status of the P2 position interface depending on the settings in P2 Device type (03.138), P1 Device Type (03.038), and Encoder Simulation Mode (03.088).

Position feedback initialisation

Some position feedback devices need to be initialised before they can provide position feedback information. For details of the initialisation required for each type of device see Position Feedback Initialized (03.076). The user can force all position feedback devices connected directly to the drive or to an option module to be initialised (see Initialise Position Feedback (03.075)). The drive also automatically initialises all position feedback devices connected to the drive position feedback interfaces immediately after power-up. An attempt is made to initialise any position feedback device that needs to be initialised when a drive reset occurs. This would happen inherently if the drive is tripped and the drive is reset to clear the trip.

It should be noted that the initialised bit for any position feedback interface in Position Feedback Initialized (03.076) is set to zero and an Encoder 7 trip is initiated if any of the parameters given below or the number of poles of the active motor are changed.

P1 Position feedback interface | P2 Position feedback interface
P1 Rotary Turns Bits (03.033) | P2 Rotary Turns Bits (03.133)
P1 Rotary Lines Per Revolution (03.034) | P2 Rotary Lines Per Revolution (03.134)
P1 Comms Bits (03.035) | P2 Comms Bits (03.135)
P1 Comms Baud Rate (03.037) | P2 Comms Baud Rate (03.137)
P1 Device Type (03.038) |
P1 Error Detection Level (03.040) (Changing bit 2 only) | P2 Error Detection Level (03.140) (Changing bit 2 only)
P1 Auto-configuration Select (03.041) | P2 Auto-configuration Select (03.141)
P1 SSI Incremental Mode (03.047) | P2 SSI Incremental Mode (03.147)
P1 SSI Binary Mode (03.048) | P2 SSI Binary Mode (03.148)
P1 Linear Feedback Select (03.051) | P2 Linear Feedback Select (03.151)
P1 Linear Comms Pitch (03.052) | P2 Linear Comms Pitch (03.152)
P1 Linear Line Pitch (03.053) | P2 Linear Line Pitch (03.153)
P1 Linear Comms And Line Pitch Units (03.054) | P2 Linear Comms And Line Pitch Units (03.154)
P1 Pole Pair Pitch (03.055) | P2 Pole Pair Pitch (03.155)
P1 Feedback Reverse (03.056) | P2 Feedback Reverse (03.156)
P1 Calculation Time (03.060) | P2 Calculation Time (03.160)
P1 Recovery Time (03.061) | P2 Recovery Time (03.161)
P1 Resolver Poles (03.065) |
P1 Resolver Excitation (03.066) (Except when changed by plus or minus 4) |
P1 Absolute Turns Recovery Enable (03.073) | P2 Absolute Turns Recovery Enable (03.173)
P1 Additional Configuration (03.074) | P2 Additional Configuration (03.174)
| P2 Status (03.172)
Motor pole pairs for the currently active motor | Motor pole pairs for the currently active motor

Encoder Simulation Output

Freeze System

The drive has two freeze functions that can capture the position from either the P1 or P2 position interface in the drive when a freeze trigger event occurs. A common freeze logic system is also provided, so that the freeze trigger events can be combined either to trigger the freeze system in the drive or to generate a freeze trigger for option modules. The freeze system is shown in the diagram below.

Position feedback interface thermistor input

Parameter | 03.001 Final Speed Reference
--- | ---
Short description | Shows the reference at the input to the speed controller
Mode | RFC‑S
Minimum | −VM_SPEED | Maximum | VM_SPEED
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, VM, ND, NC, PT

Final Speed Reference (03.001) shows the reference at the input to the speed controller, which is the sum of the Post Ramp Reference (02.001) if the ramp output is not disabled and the hard speed reference (if enabled).

Parameter | 03.002 Speed Feedback
--- | ---
Short description | Displays the speed feedback from the selected feedback source
Mode | RFC‑S
Minimum | −VM_SPEED | Maximum | VM_SPEED
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, VM, ND, NC, PT

The speed feedback can be selected with Motor Control Feedback Select (03.026) to be taken from either of the drive position feedback interfaces or from a position feedback interface in a position feedback category option module. It is also possible to select sensorless speed feedback with RFC Feedback Mode (03.024). Speed Feedback (03.002) shows the level of the speed feedback selected for the speed controller.

The FI attribute is set for this parameter, so display filtering is active when this parameter is viewed with one of the drive keypads. The value held in the drive parameter (accessible via comms or an option module) does not include this filter, but is a value that is obtained over a sliding 16ms period to limit the ripple. The speed feedback includes quantisation ripple given by the following equation in rpm:

> Ripple in Speed Feedback (03.002) = 60 / 16ms / Position resolution

The ripple for a linear system is given by the following equation in mm/s:

> Ripple in Speed Feedback (03.002) = Pole pitch in mm / 16ms / Position resolution

The position resolution for each type of feedback device is defined in the table below.

Position feedback device | Position resolution
AB, AB Servo | 4 x lines per revolution or pole pitch
FD, FR, FD Servo, FR Servo | 2 x lines per revolution or pole pitch
SC, SC Hiperface, SC EnDat, SC SSI, SC Servo | 1024 x sine waves per revolution or pole pitch
EnDat, SSI, BiSS, EnDat 3 | Comms bits per revolution or pole pitch
Resolver | See P1 Resolver Excitation (03.066)

For example the ripple in Speed Feedback (03.002) when a 4096 line AB type encoder is used is 0.23rpm. It should be noted that no filtering is applied to the speed feedback used by the speed controller or for the position feedback reference system unless the feedback filter for that particular interface is activated by putting a non-zero value in the appropriate set up parameter (i.e. P1 Feedback Filter (03.042) for the P1 drive position feedback interface). The diagram below shows the filtering applied to the speed feedback when this is taken from the P1 drive position feedback interface.

The speed feedback ripple seen by the speed controller and the position feedback reference is given by the following equations when the filter set up value P1 Feedback Filter (03.042) = 0.

> Ripple for a rotary system in rpm = 60 / Speed controller sample time / Position resolution

> Ripple for a linear system in mm/s = Pole pitch in mm / Speed controller sample time / Position resolution

The speed controller sample time is 250µs. If the filter set up value is non-zero the ripple is given by:

> Ripple for a rotary system in rpm = 60 / Filter time / Position resolution

> Ripple for a linear system in mm/s = Pole pitch in mm / Filter time / Position resolution

The description so far covers the P1 drive position feedback interface. Similar filtering is provided with the P2 drive position feedback interface and with position feedback interfaces in position feedback category option modules.

It is not advisable to use the speed feedback filter unless it is specifically required for high inertia applications with high controller gains, or if commutation signals alone are used for feedback, because the filter has a non-linear transfer function. It is preferable to use the current demand filters (Current Reference Filter 1 Time Constant (04.012) or Current Reference Filter 2 Time Constant (04.023)) as these are linear first order filters that provide filtering on noise generated from both the speed reference and the speed feedback. It should be noted that any filtering included within the speed controller feedback loop, either on the speed feedback or the current demand, introduces a delay and limits the maximum bandwidth of the controller for stable operation.

The speed ripple seen by the speed controller can be quite high in some cases, for example with a 4096 line encoder the speed ripple is 14.6rpm with a sample time of 250µs. This causes high frequency torque ripple and acoustic motor noise. These effects increase with the level of speed feedback ripple and with the gains used in the speed controller. Therefore high speed feedback ripple usually limits the maximum possible gain settings for the speed controller, and so a position feedback device with high position resolution is usually required for a system with high dynamic performance or stiffness. It should be noted that the ripple caused by feedback quantisation and does not define speed feedback resolution. The speed controller accumulates all pulses from the position feedback, and so the speed controller resolution is not limited by the feedback, but by the resolution of the speed reference.

Parameter | 03.003 Speed Error
--- | ---
Short description | Displays the difference between the Final Speed Reference and the Speed Feedback
Mode | RFC‑S
Minimum | −VM_SPEED | Maximum | VM_SPEED
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, VM, ND, NC, PT

The speed error is the difference between the Final Speed Reference (03.001) and the Speed Feedback (03.002), and does not include the effect of the differential term in the speed controller feedback branch.

Parameter | 03.004 Speed Controller Output
--- | ---
Short description | Displays the output from the speed controller
Mode | RFC‑S
Minimum | −VM_TORQUE_CURRENT | Maximum | VM_TORQUE_CURRENT
Default |  | Units | %
Type | 16 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, VM, ND, NC, PT

The output of the speed regulator is a torque demand given as a percentage of rated motor torque. It should be noted that this will be modified to take into account in the level of motor flux if field weakening is active before it is converted into the Final Current Reference (04.004).

Parameter | 03.005 Zero Speed Threshold
--- | ---
Short description | Set to the required zero speed threshold
Mode | RFC‑S
Minimum | 0 | Maximum | 200
Default | 5 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

If the Speed Feedback (03.002) is at or below the level defined by this parameter in either direction Zero Speed (10.003) = 1, otherwise Zero Speed (10.003) = 0.

Parameter | 03.006 At Speed Lower Limit
--- | ---
Short description | Set to the required minimum at speed threshold
Mode | RFC‑S
Minimum | 0 | Maximum | 33000
Default | 5 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

At Speed (10.006) is set if the Speed Feedback (03.002) is on the boundaries or within the at-speed window. Above Set Speed (10.007) and Below Set Speed (10.005) are set if the feedback is above or below the window respectively.

If Absolute At Speed Select (03.009) = 0 reference window mode is used.
The "at speed" condition is true if Reference On (01.011) =1 and,

> (|Pre-ramp Reference (01.003)| - At Speed Lower Limit (03.006)) ≤ |Speed Feedback (03.002)| ≤ (|Pre-ramp Reference (01.003)| + At Speed Upper Limit (03.007))

(If the lower limit is less than zero then zero is used as the lower limit.)

If Absolute At Speed Select (03.009) = 1 absolute window mode is used.
The "at speed" condition is true if Reference On (01.011) =1 and,

> At Speed Lower Limit (03.006) ≤ |Speed Feedback (03.002)| ≤ At Speed Upper Limit (03.007)

Parameter | 03.007 At Speed Upper Limit
--- | ---
Short description | Set to the required maximum at speed threshold
Mode | RFC‑S
Minimum | 0 | Maximum | 33000
Default | 5 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

See At Speed Lower Limit (03.006).

Parameter | 03.008 Over Speed Threshold
--- | ---
Short description | Set to the required over speed threshold
Mode | RFC‑S
Minimum | 0 | Maximum | 33000
Default | 0 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

If Over Speed Threshold (03.008) is set to a non-zero value it defines the over speed threshold. If the Speed Feedback (03.002) exceeds this threshold in either direction an Over Speed trip is produced. If Over Speed Threshold (03.008) is set to 0.0 the threshold is based on the variable minimum/maximum for the references and is equal to 1.2 x VM_SPEED_FREQ_REF[MAX]. As the over-speed trip provides the ultimate protection against against the motor operating beyond the maximum allowable speed, the trip function is time deterministic and will disable the drive within 4ms of the over-speed condition being detected.

The motor speed and the motor voltage can be monitored to detect if the motor is accelerating in an uncontrolled way because position feedback is being used and the Position Feedback Phase Angle (03.025) has not been set up correctly. If the Over Speed Threshold (03.008) = 0 then position feedback phase angle error monitoring is enabled and a Phasing Error trip is initiated if a failure is detected. If the Over Speed Threshold (03.008) is not equal to 0 this feature is disabled, and the over-speed trip is the only protection against high motor speed due to an incorrect value of Position Feedback Phase Angle (03.025). It should be noted that phase angle error monitoring is not possible with high saliency motors, and so if Active Saliency Torque Mode (05.066) = 1 then phase angle error detection is suppressed and the over-speed trip must be used to provide protection.

If sensorless control is being used, a Phasing Error trip is also initiated if loss of control is detected. This trip is also suppressed if Over Speed Threshold (03.008) is set to a non-zero value.

Parameter | 03.009 Absolute At Speed Select
--- | ---
Short description | Indicates when the motor is running at speed
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See At Speed Lower Limit (03.006).

Parameter | 03.010 Speed Controller Proportional Gain Kp1
--- | ---
Short description | Defines the proportional gain for the speed controller
Mode | RFC‑S
Minimum | 0.0000 | Maximum | 200.0000
Default | 0.0100 | Units | s/rad
Type | 32 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 4
Coding | RW

The diagram below shows a generalised representation of the speed controller. The controller includes a feed forward proportional gain (Kp), a feed forward integral gain (Ki), and a differential feedback gain (Kd). The description here refers to the first set of gains for motor map 1 (Speed Controller Proportional Gain Kp1 (03.010), Speed Controller Integral Gain Ki1 (03.011) and Speed Controller Differential Feedback Gain Kd1 (03.012)). See Speed Controller Gain Select (03.016) on how to select a different set of gains.

Proportional gain (Kp) - Speed Controller Proportional Gain Kp1 (03.010)
If Kp is non-zero and Ki is zero the controller will only have a proportional term, and there must be a speed error to produce a torque reference. Therefore, as the motor load increases there will be a difference between the reference and actual speeds. This effect, called regulation, depends on the level of the proportional gain, the higher the gain the smaller the speed error for a given load. If the proportional gain is too high either the acoustic noise produced due to speed feedback quantisation becomes unacceptable, or the closed-loop stability limit is reached.

Integral gain (Ki) - Speed Controller Integral Gain Ki1 (03.011)
The integral gain is provided to prevent speed regulation. The error is accumulated over a period of time and used to produce the necessary torque reference without any speed error. Increasing the integral gain reduces the time taken for the speed to reach the correct level and increases the stiffness of the system, i.e. it reduces the positional displacement produced by applying a load torque to the motor. Unfortunately increasing the integral gain also reduces the system damping giving overshoot after a transient. For a given integral gain the damping can be improved by increasing the proportional gain. A compromise must be reached where the system response, stiffness and damping are all adequate for the application. The integral term is implemented in the form of ∑(Ki x error), and so the integral gain can be changed when the controller is active without causing large transients on the torque reference.

Differential gain (Kd) - Speed Controller Differential Feedback Gain Kd1 (03.012)
The differential gain is provided in the feedback of the speed controller to give additional damping. The differential term is implemented in a way that does not introduce excessive noise normally associated with this type of function. Increasing the differential term reduces the overshoot produced by under-damping, however for most applications the proportional and integral gains alone are sufficient. It should be noted that the differential term is limited internally so that it is ineffective if speed in rpm x Kd x Ki is greater than 170.

To analyse the performance of the speed controller it may be represented as an s-domain model as shown below.

Kc' is the conversion between the speed controller output and the torque producing current reference. A value of unity at the output of the speed controller gives a torque producing current equal to Kc'. The drive automatically compensates the torque producing current reference for flux variations in field weakening, and so Kc' can be assumed to have a constant value even in field weakening. Kc' = Full Scale Current Kc (11.061) x 0.45.

Kt is the torque constant of the motor (i.e. torque in Nm per amp of torque producing current). This value is normally available from the manufacturer for a permanent magnet motor, however, for induction motors the value must be calculated from the motor parameters. In RFC-A mode this calculation is performed by the drive and the result is stored in Torque Per Amp (05.032).

L(s) is the transfer function of the load.

The speed controller calculations are provided for a rotary application. However, for a linear application it is possible to set Torque Per Amp (05.032) to the force per amp and the Motor And Load Inertia (03.018) to the mass, and all the rotary system equations still apply.

It should be noted that the gain levels are compatible with those in Unidrive SP. The internal resolution of the intergral gain parameter is twice that of Unidrive SP. In most applications this makes no difference to the performance, however, with Unidrive SP the internal value is zero (the integral term disabled) if the user parameter is less than 0.05. In Unidrive M the internal integral gain would be zero if Speed Controller Integral Gain Ki1 (03.011) is less than 0.03. However, if Speed Controller Integral Gain Ki1 (03.011) is non-zero and less than 0.03 (i.e. 0.01 or 0.02) the internal value is one, so that the integral term remains active, unless the user deliberately disables this term by setting Speed Controller Integral Gain Ki1 (03.011) to zero.

Parameter | 03.011 Speed Controller Integral Gain Ki1
--- | ---
Short description | Defines the integral gain for the speed controller
Mode | RFC‑S
Minimum | 0.00 | Maximum | 655.35
Default | 1.00 | Units | s²/rad
Type | 16 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 2
Coding | RW, BU

See Speed Controller Proportional Gain Kp1 (03.010).

Parameter | 03.012 Speed Controller Differential Feedback Gain Kd1
--- | ---
Short description | Defines the differential gain for the speed controller
Mode | RFC‑S
Minimum | 0.00000 | Maximum | 0.65535
Default | 0.00000 | Units | 1/rad
Type | 16 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 5
Coding | RW, BU

See Speed Controller Proportional Gain Kp1 (03.010).

Parameter | 03.013 Speed Controller Proportional Gain Kp2
--- | ---
Short description | Defines a 2nd proportional gain for the speed controller
Mode | RFC‑S
Minimum | 0.0000 | Maximum | 200.0000
Default | 0.0100 | Units | s/rad
Type | 32 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 4
Coding | RW

See Speed Controller Proportional Gain Kp1 (03.010).

Parameter | 03.014 Speed Controller Integral Gain Ki2
--- | ---
Short description | Defines a 2nd integral gain for the speed controller
Mode | RFC‑S
Minimum | 0.00 | Maximum | 655.35
Default | 1.00 | Units | s²/rad
Type | 16 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 2
Coding | RW, BU

See Speed Controller Proportional Gain Kp1 (03.010).

Parameter | 03.015 Speed Controller Differential Feedback Gain Kd2
--- | ---
Short description | Defines a 2nd differential gain for the speed controller
Mode | RFC‑S
Minimum | 0.00000 | Maximum | 0.65535
Default | 0.00000 | Units | 1/rad
Type | 16 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 5
Coding | RW, BU

See Speed Controller Proportional Gain Kp1 (03.010).

Parameter | 03.016 Speed Controller Gain Select
--- | ---
Short description | Set to 1 to enable the 2nd set of speed controller proportional, integral and differential gains
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 0
Coding | RW

If Speed Controller Gain Select (03.016) = 0 then Kp1, Ki1 and Kd1 are used as the speed controller gains. These gains are given by Speed Controller Proportional Gain Kp1 (03.010), Speed Controller Integral Gain Ki1 (03.011) and Speed Controller Differential Feedback Gain Kd1 (03.012) if motor map 1 is selected (i.e. Select Motor 2 Parameters (11.045) = 0), or M2 Speed Controller Proportional Gain Kp1 (21.017), M2 Speed Controller Integral Gain Ki1 (21.018) and M2 Speed Controller Differential Feedback Gain Kd1 (21.019) if motor map 2 is selected (i.e. Select Motor 2 Parameters (11.045) = 1). If Speed Controller Gain Select (03.016) = 1 then Kp2, Ki2 and Kd2 are used as the speed controller gains. These gains are given by Speed Controller Proportional Gain Kp2 (03.013), Speed Controller Integral Gain Ki2 (03.014) and Speed Controller Differential Feedback Gain Kd2 (03.015). When Speed Controller Gain Select (03.016) is changed the gains are changed smoothly between the old and new values over a period of 250ms. This allows the system gains to be switched between two different sets of values without causing significant torque transients.

Parameter | 03.017 Speed Controller Set-up Method
--- | ---
Short description | Defines how the speed controller is set up
Mode | RFC‑S
Minimum | 0 | Maximum | 7
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | 1s read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Disabled
1 | Bandwidth
2 | Comp Angle
3 | Kp Gain Times 16
4 | Low Performance
5 | Std Performance
6 | High Performance
7 | First Order

0: Disabled
When Speed Controller Set-up Method (03.017) is at its default value of 0, its functions are disabled and it has no effect.

1: Bandwidth set-up
If the load is predominantly a constant inertia and constant torque, the drive can calculate the required speed loop gain values, provided the Motor And Load Inertia (03.018) and the Torque Per Amp (05.032) are set-up correctly. If Speed Controller Set-up Method (03.017) = 1 the gain values are calculated to give the required Bandwidth (03.020) and Damping Factor (03.021). The calculated values for Kp and Ki are written to Speed Controller Proportional Gain Kp1 (03.010) and Speed Controller Integral Gain Ki1 (03.011) once per second. The Speed Controller Differential Feedback Gain Kd1 (03.012) is not affected. The gains are calculated from a linear model assuming a pure inertia load, not including unwanted delays in the speed and current controllers. The following equations are used by the drive to calculate the gains.

> Ki = J / (Kc' x Kt) x (2π x ωbw / Kbw)2

> Kp = 2 ξ √[ (Ki x J) / (Kc' x Kt) ]

where:
Kc' = Full Scale Current Kc (11.061) x 0.45
J = Motor And Load Inertia (03.018)
Kt = Torque Per Amp (05.032)
ωbw = Bandwidth (03.020)
ξ = Damping Factor (03.021)
Kwb = √[ (2ξ2 + 1) +√( (2ξ2 + 1)2 + 1) ]

2: Compliance angle set-up
If Speed Controller Set-up Method (03.017) = 2 the speed controller gains are set up based on the required Compliance Angle (03.019) and Damping Factor (03.021)
based on the following equations.

> Ki = 1 / αcomp(rs-1)

> Kp = 2 ξ √[ (Ki x J) / (Kc' x Kt) ]

where:
Kc' = Full Scale Current Kc (11.061) x 0.45
J = Motor And Load Inertia (03.018)
Kt = Torque Per Amp (05.032)
αcomp = Compliance Angle (03.019)
ξ = Damping Factor (03.021)

3: Kp gain times 16
If Speed Controller Set-up Method (03.017) = 3 the selected proportional gain used by the drive is multiplied by 16. This feature was provided in Unidrive SP because the range of the proportional gain parameters was limited. The range has now been increased to allow higher gains to be selected, and so this feature is no longer necessary, but is provided for compatibility with Unidrive SP. It should be noted that if this feature is used the value of gain used by the speed controller (i.e. Speed Controller Proportional Gain Kp1 (03.010) x 16) is limited internally to the maximum for Speed Controller Proportional Gain Kp1 (03.010).

4-6: Low, Standard or High performance
If Speed Controller Set-up Method (03.017) is set to a value from 4 to 6 the Speed Controller Proportional Gain Kp1 (03.010) and Speed Controller Integral Gain Ki1 (03.011) are automatically set up to give the bandwidths given in the table below and a damping factor of unity. These settings give low, standard or high performance.

Speed Controller Set-up Method (03.017) | Performance | Bandwidth
4 | Low | 5Hz
5 | Standard | 25Hz
6 | High | 100Hz

7: First order characteristic
If Speed Controller Set-up Method (03.017) = 7 then Speed Controller Proportional Gain Kp1 (03.010), Speed Controller Integral Gain Ki1 (03.011) and Speed Controller Differential Feedback Gain Kd1 (03.012) are set up to give a closed-loop speed controller response that approximates to a first order system with a transfer function of 1 / (sτ + 1), where τ = 1/ωbw and ωbw = 2π x Bandwidth (03.020). In this case the damping factor is meaningless, and Damping Factor (03.021) and Compliance Angle (03.019) have no effect. The following equations are used by the drive to calculate the gains.

> Ki = J / (Kc' x Kt) x (2π x ωbw / 2)2

> Kp = 2 √[ (Ki x J) / (Kc' x Kt) ]

> Kd = Kp / 4Ki

where:
Kc' = Full Scale Current Kc (11.061) x 0.45
J = Motor And Load Inertia (03.018)
Kt = Torque Per Amp (05.032)
ωbw = Bandwidth (03.020)

Parameter | 03.018 Motor And Load Inertia
--- | ---
Short description | Defines the inertia of the motor and the load for use in calculating the speed controller gains
Mode | RFC‑S
Minimum | 0.00000 | Maximum | 1000.00000
Default | 0.00000 | Units | kgm²
Type | 32 Bit User Save | Update Rate | 1s read
Display Format | Standard | Decimal Places | 5
Coding | RW

The Motor And Load Inertia (03.018) represents the total inertia driven by the motor. This is used to set the speed controller gains (see Speed Controller Set-up Method (03.017)) and to provide torque feed forwards during acceleration when required (see Torque Mode Selector (04.011)).

It is possible to measure the inertia as part of the auto-tune process (see Auto-tune (05.012)).

Parameter | 03.019 Compliance Angle
--- | ---
Short description | Defines the required angular displacement when the drive delivers a torque producing current equivalent to drive rated current
Mode | RFC‑S
Minimum | 0.0 | Maximum | 360.0
Default | 4.0 | Units | °
Type | 16 Bit User Save | Update Rate | 1s read
Display Format | Standard | Decimal Places | 1
Coding | RW

The Compliance Angle (03.019) is the required angular displacement when the drive delivers a torque producing current equivalent to Kc', i.e. Full Scale Current Kc (11.061) x 0.45, with no field weakening. The value of this parameter is used to automatically determine the speed controller gains if required. See Speed Controller Set-up Method (03.017).

Parameter | 03.020 Bandwidth
--- | ---
Short description | Defines the theoretical 3dB point on the closed-loop gain characteristic of the speed controller as a second order system
Mode | RFC‑S
Minimum | 1 | Maximum | 1000
Default | 10 | Units | Hz
Type | 16 Bit User Save | Update Rate | 1s read
Display Format | Standard | Decimal Places | 0
Coding | RW

The Bandwidth (03.020) is defined as the theoretical 3dB point on the closed-loop gain characteristic of the speed controller as a second order system. At this point the phase shift is approximately 60°. The value of Bandwidth (03.020) is used to automatically determine the speed controller gains if required. See Speed Controller Set-up Method (03.017).

Parameter | 03.021 Damping Factor
--- | ---
Short description | Defines the factor for the response of the system to a torque transient
Mode | RFC‑S
Minimum | 0.0 | Maximum | 10.0
Default | 1.0 | Units |
Type | 8 Bit User Save | Update Rate | 1s read
Display Format | Standard | Decimal Places | 1
Coding | RW

Damping Factor (03.021) defines this factor for the response of the system to a torque transient, and so if the Damping Factor (03.021) is unity, the response to a load torque transient is critically damped. The closed-loop step response of the speed controller gives approximately 10% overshoot with unity damping factor. Damping Factor (03.021) is used to automatically determine the speed controller gains if required. See Speed Controller Set-up Method (03.017).

Parameter | 03.022 Hard Speed Reference
--- | ---
Short description | Defines a speed reference value which does not pass through the ramp system
Mode | RFC‑S
Minimum | −VM_SPEED_FREQ_REF | Maximum | VM_SPEED_FREQ_REF
Default | 0.0 | Units |
Type | 32 Bit User Save | Update Rate | 250µs read
Display Format | Standard | Decimal Places | 1
Coding | RW, VM

The Hard Speed Reference (03.022) is a reference value which does not pass through the ramp system, but is added directly to the Post Ramp Reference (02.001).The Hard Speed Reference (03.022) is only added when selected by the Hard Speed Reference Select (03.023) and the Reference On (01.011) is active.

The Advanced Motion Controller (AMC) or an application option module can write to Hard Speed Reference (03.022) using a high resolution internal routing method. If this is case the value shown in Hard Speed Reference (03.022) will reflect the speed written by the internal routing method, but it will be updated at a slower rate than what the drive is actually using.

Parameter | 03.023 Hard Speed Reference Select
--- | ---
Short description | Set to 1 to enable the use of the hard speed reference
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Hard Speed Reference (03.022).

Parameter | 03.024 RFC Feedback Mode
--- | ---
Short description | Defines the method of feedback used for the speed controller
Mode | RFC‑S
Minimum | 0 | Maximum | 3
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | 4ms read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Feedback
1 | Sensorless
2 | Feedback NoMax
3 | Sensorless NoMax

RFC Feedback Mode (03.024), which can be changed even when the motor is running, selects the feedback method used to provide position feedback to control the motor. The actual feedback method being used at any time is given by Sensorless Mode Active (03.078). When sensorless mode is used, a filter with a 4ms time constant is automatically included in the speed feedback as this is required for this system to operate correctly. The possible speed controller bandwidth will be reduced by a factor of approximately 10 compared with the bandwidth possible with a position feedback device. The maximum and minimum for the speed references are limited by the VM_POSITIVE_REF_CLAMP variable minimum/maximum which prevents the speed from exceeding the level where the position feedback cannot be interpreted correctly. This limit is disabled if RFC Feedback Mode (03.024) is 2 or 3, so that it is possible to change between operation with or without position feedback if the speed range needs to be extended beyond the limit of the position feedback device. Care should be taken not to exceed a speed that would damage the position feedback device.

0: Position feedback
RFC mode is active using the position feedback selected Motor Control Feedback Select (03.026) to control the motor.

1: Sensorless
RFC mode using a sensorless algorithm to provide position feedback, is used to control the motor.
NOTE: Sensorless mode can only be used with permenant magnet motors and not with synchronous reluctance motors.

2: Position feedback with no maximum speed limit
RFC mode with position feedback selected with Motor Control Feedback Select (03.026)) is used to control the motor. The maximum reference limit is disabled.

3: Sensorless with no maximum speed limit
RFC mode using a sensorless algorithm to provide position feedback, is used to control the motor. The maximum reference limit is disabled.

It should be noted for sensorless mode to operate correctly using the injection method (RFC Low Speed Mode (05.064)) there is a mimum difference required between Ld and Lq in the motor otherwise a trip is initated. See Inductance for details.

Parameter | 03.025 Position Feedback Phase Angle
--- | ---
Short description | Defines the phase angle between the rotor flux and the feedback position and must be set up correctly for the drive to control the motor correctly
Mode | RFC‑S
Minimum | 0.0 | Maximum | 359.9
Default |  | Units | °
Type | 16 Bit User Save | Update Rate | 1ms read
Display Format | Standard | Decimal Places | 1
Coding | RW, ND

The phase angle between the rotor flux and the feedback position must be set up correctly for the drive to control the motor correctly. If the phase angle is known it can be set in Position Feedback Phase Angle (03.025) by the user. Alternatively the drive can automatically measure the phase angle by performing a phasing test (see Auto-tune (05.012)). When the test is complete the new value is automatically written to Position Feedback Phase Angle (03.025). Position Feedback Phase Angle (03.025) can be modified at any time and becomes effective immediately. Position Feedback Phase Angle (03.025) has a factory default value of 0.0, but is not affected when defaults are loaded by the user.

The alignment required for zero position feedback phase angle (i.e. Position Feedback Phase Angle (03.025) = 0.0) is given below for different feedback devices. Although the drive output phase rotation and position feedback direction of rotation can be reversed, in the examples given forward rotation of the motor is produced when Vu leads Vv leads Vw, and the position feedback direction has not been reversed. Although it is not essential, forward rotation of a motor is normally defined as clockwise when looking at the motor shaft end. When the motor is rotating forwards the motor speed is shown as positive and the position increases.

AB Servo, FD Servo, FR Servo, SC Servo
The alignment required between the no-load motor voltages and the commutation signals for Position Feedback Phase Angle (03.025) = 0.0 is shown in the diagram below. It should be noted that if the encoder is ajusted with respect to the rotor so that the UVW signals are moved to the right with respect to the voltages the angle in Position Feedback Phase Angle (03.025) is increased from zero. If the encoder is retarded the angle changes to 359.9 and then reduces towards zero.

The encoder can be aligned statically by connecting the motor to a d.c. power supply as shown.

The motor will move to one of a number of positions defined by the number of motor pole pairs (i.e. 3 positions for a six pole motor, etc.). The encoder should be adjusted so that the U commutation signal is high, W is low and V is toggling in one of these positions.

Any other feedback device
The alignment required between the no-load motor voltages and the position feedback (i.e. P1 Position (03.029) for the drive P1 position feedback interface) with Position Feedback Phase Angle (03.025) = 0.0 is shown in the diagram below for a 2 or 4 pole motor. For higher numbers of poles the zero position should still be aligned as shown, but the one electrical cycle shown corresponds to 360° / (Number of poles / 2). It should be noted that if the position feedback device adjusted with respect to the rotor and the zero position is moved to the right with respect to the voltages Position Feedback Phase Angle (03.025) is increased from zero. If the position feedback is retarded Position Feedback Phase Angle (03.025) changes to 359.9 and then reduces towards zero.

The position feedback device can be aligned statically by connecting the motor to a d.c. power supply as already shown. The motor will move to one of a number of positions defined by the number of motor poles (i.e. 3 positions for a six pole motor, etc.). The position feedback device should be adjusted so that the position displayed by the drive is (n x 65536) / (Number of poles / 2), where n = 0, 1, etc..

The diagram below shows the relationship between the position feedback signals and P1 Position (03.029) for a 2-pole resolver. For higher numbers of poles the zero position is the same but the cycle repeats multiple times per revolution as the number of poles is increased. Where the waveforms are at their highest positive level they are maximum and in phase with the excitation, and where they are at their lowest negative level they are maximum and 180o out of phase with the excitation.

Parameter | 03.026 Motor Control Feedback Select
--- | ---
Short description | Defines the source of position feedback
Mode | RFC‑S
Minimum | 0 | Maximum | 7
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | P1 Drive
1 | P2 Drive
2 | P1 Slot1
3 | P2 Slot1
4 | P1 Slot2
5 | P2 Slot2

Motor Control Feedback Select (03.026) should be used to select the position feedback interface for motor control. If the feedback interface does not exist then the drive will produce an Encoder 9 trip if it is enabled. Note that if RFC Feedback Mode (03.024) is set to 1 or 3 to select sensorless control then this trip is suppressed.

Parameter | 03.027 P1 Speed Feedback
--- | ---
Short description | Displays the speed feedback from device P1
Mode | RFC‑S
Minimum | −VM_SPEED | Maximum | VM_SPEED
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, VM, ND, NC, PT

Provided the set-up parameters for the position feedback device connected to the drive P1 position interface are correct P1 Speed Feedback (03.027) shows the speed derived from the feedback. The speed is given in mm/s if P1 Linear Feedback Select (03.051) = 1 and Linear Speed Select (01.055) = 1, otherwise it is given in rpm. The value shown is measured over a 16ms sliding window period, and so the ripple in this value is as defined for Speed Feedback (03.002).

Parameter | 03.028 P1 Revolution/Pole Pitch Counter
--- | ---
Short description | Displays the revolution/pole pitch counter from device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default |  | Units |
Type | 16 Bit Power Down Save | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT, BU

P1 Revolution/Pole Pitch Counter (03.028), P1 Position (03.029) and P1 Fine Position (03.030) combined give the encoder position with a resolution of 1/232 of a revolution/pole pitch as a 48 bit number. If a rotary position feedback device is being used (P1 Linear Feedback Select (03.051) = 0) then these quantities relate directly to the rotary position of the feedback device. If a linear feedback device is used then one revolution or pole pitch relates to the distance given by P1 Pole Pair Pitch (03.055).

Provided the position feedback interface set-up parameters are correct, the position is always converted to units of 1/232 of a revolution/pole pitch, but some parts of the value may not be relevant depending on the resolution of the feedback device. For example a 1024 line digital encoder produces 4096 counts per revolution, and so the position is represented by the bits in the shaded area only.

When the position feedback moves by more than one revolution or pole pitch the P1 Revolution/Pole Pitch Counter (03.028) increments or decrements in the form of a sixteen bit roll-over counter. If an absolute position feedback device (except AB Servo, FD Servo, FR Servo, SC Servo) is used the position is initialised at power-up and each time the encoder is subsequently initialised with the absolute position including the revolution count if a multi-turn absolute rotary encoder is used, or the pole pitch count if an absolute linear encoder is used. To avoid showing turns values that are outside the range of the encoder any bits beyond the turns information are normally masked. For example, if the encoder provides 12 bits of turns information, then the most significant 4 bits of the revolutions are always zero. If a single turn encoder is used all the bits of the revolutions are zero. To remove this masking P1 Absolute Turns Recovery Enable (03.073) should be set to one. In addition to removing the mask, the extended turns value is retained on power-down and will be recovered on power-up. See P1 Absolute Turns Recovery Enable (03.073) for more details.

The position interface parameter descriptions cover rotary and linear applications, but the revolutions or pole pitches are always referred to as turns.

Parameter | 03.029 P1 Position
--- | ---
Short description | Displays the position feedback from device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default |  | Units |
Type | 16 Bit Power Down Save | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT, BU

See P1 Revolution/Pole Pitch Counter (03.028).

Parameter | 03.030 P1 Fine Position
--- | ---
Short description | Displays the fine position feedback from device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default |  | Units |
Type | 16 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT, BU

See P1 Revolution/Pole Pitch Counter (03.028).

Parameter | 03.031 P1 Marker Mode
--- | ---
Short description | Defines the marker mode for device P1
Mode | RFC‑S
Minimum | 0 (Display: 00000) | Maximum | 31 (Display: 11111)
Default | 4 (Display: 00100) | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Binary | Decimal Places | 0
Coding | RW

P1 Device Type (03.038): AB, FD, FR, AB Servo, FD Servo, FR Servo
Each position feedback device produces incremental signals which are counted in hardware. If P1 Marker Mode (03.031) = 0 the following occurs when a marker event is produced by the Z1 input:

1. P1 Position (03.029) and P1 Fine Position (03.030) are reset to zero.
2. The bits in P1 Normalised Position (03.058) related to P1 Position (03.029) and P1 Fine Position (03.030) are reset to zero
3. P1 Marker Flag (03.032) is set to one.

The marker is a hardware function, and so the position appears as though it is reset at the marker event time even if this is between control system sample points. It should be noted that the marker event occurs on the rising edge of the marker pulse if the position change over the last sample was positive or on the falling edge if the position change over the last sample was negative. This ensures that the marker event occurs at the same physical location for either direction of rotation.

The action taken when a marker event occurs can be modified by setting the bits of P1 Marker Mode (03.031) as described in the table below.

Bit | Effect of setting bit to one
0 | No action is taken unless the marker flag is zero before the marker event occurs
1 | P1 Revolution/Pole Pitch Counter (03.028) and the whole of P1 Normalised Position (03.058) are also set to zero on a marker event
2 | P1 Revolution/Pole Pitch Counter (03.028), P1 Position (03.029), P1 Fine Position (03.030) and the related part of P1 Normalised Position (03.058) are not reset. (This overrides bit 1.) P1 Normalised Position (03.058) is transferred to P1 Normalised Marker Position (03.059) and P1 Marker Flag (03.032) is set to one.

The marker input can be used for a standard type marker function or alternatively it can be used as an additional freeze input for the P1 position feedback interface.

P1 Device Type (03.038): SC, SC Servo
The marker function operates in the same way as for the digital incremental encoders. The marker is a hardware function which operates on a digital version of the sine wave signals produced by comparators that only indicate the polarity. Therefore the resolution of the marker actions is only as accurate as the zero crossings of the sine wave signals.

P1 Device Type (03.038): SC SC
The marker function operates in the same way as for the digital incremental encoders. The marker is a hardware function which operates on a digital version of the sine wave signals produced by comparators that only indicate the polarity. Therefore the resolution of the marker actions is only as accurate as the zero crossings of the sine wave signals. If a marker signal is available and connected it can be used to improve the absolute accuracy, compared to the accuracy provided by the single cycle sine waves. Bits 3 has an effect whichever position feedback device is selected, but is only really applicable to this type of device. Bit 4 only has any effect with this type of position feedback device.

Bit | Effect of setting bit to one
3 | If this bit is 0 the state of the marker is only undefined when the differential input is in the range from -200mV to 200mV. The marker pulse is only guaranteed to be recognised if it is at least 500ns wide. This setting is used for most encoders with standard level marker pulses. If this bit is set to 1 the undefined state region is reduced to the range from -30mV to 30mV. The marker pulse is only guaranteed to be recognised if it is at least 10us wide. The smaller undefined region is required for position feedback devices that produce a small marker pulse, such as the Heidenhain ERN1387 encoder. Note that the reduced undefined region is only provided for position feedback interface P1 and that this bit in P2 Marker Mode (03.131) has no effect.
4 | This bit is primarily intended to disable the marker function for SCSC type encoders, however, if this bit is set to 1 it disables the marker function for any type of encoder with a marker input. When an SCSC type encoder is used and this bit is left at its default of 0 the marker is used to improve the accuracy of the absolute position. If it is set to 1 the single sine wave signals alone are used to define the absolute position. It is important to set this bit to 1 if a marker is not being used to ensure that noise on the marker input does not falsely modify the absolute position.

P1 Device Type (03.038): Any other device type
The marker function cannot be used and P1 Marker Mode (03.031) has no effect.

Parameter | 03.032 P1 Marker Flag
--- | ---
Short description | Indicates when a marker event occurs
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

P1 Marker Flag (03.032) is set to one when a marker event occurs. The flag must be cleared by the user.

Parameter | 03.033 P1 Rotary Turns Bits
--- | ---
Short description | Defines the number of rotary turns bits for device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 16
Default | 16 | Units |
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Rotary Turns Bits (03.033) normally only has any effect if the position feedback interface is being used with a rotary device (i.e. P1 Linear Feedback Select (03.051) = 0).

P1 Device Type (03.038): SC Hiperface, SC EnDat, SC SSI, EnDat, BISS, SSI, SC BiSS, EnDat 3
P1 Rotary Turns Bits (03.033) is used to determine the number of bits within the comms messages from the position feedback device that represent turns. For a single turn encoder P1 Rotary Turns Bits (03.033) must be set to zero. The most significant bits in P1 Revolution/Pole Pitch Counter (03.028) that are not included in the turns information provided by the encoder comms are held at zero. If P1 Rotary Turns Bits (03.033) = 0 (single turn encoder) the whole of P1 Revolution/Pole Pitch Counter (03.028) is held at zero. The number of bits of position information within one revolution for a rotary device are calculated from P1 Rotary Turns Bits (03.033) and P1 Comms Bits (03.035). If the resulting value is greater than 32 it is limited to 32.

Some SSI encoders include leading zeros before the turns information and in this case the number of turns bits should include the leading zeros. Some BiSS encoders include zero padding either before or after the turns information (see P1 Additional Configuration (03.074)). P1 Rotary Turns Bits (03.033) should include the actual turns bits and the additional padding.

P1 Device Type (03.038): Any other device type
It is sometimes desirable to mask off the most significant bits of P1 Revolution/Pole Pitch Counter (03.028), but this does not have to be done for the drive to function correctly. If P1 Rotary Turns Bits (03.033) = 0 the whole of P1 Revolution/Pole Pitch Counter (03.028) is held at zero. If P1 Rotary Turns Bits (03.033) has any other value it indicates the number of bits in P1 Revolution/Pole Pitch Counter (03.028) that are not held at zero. For example, if P1 Rotary Turns Bits (03.033) = 5, then P1 Revolution/Pole Pitch Counter (03.028) counts up to 31 before being reset.

The description above is for normal operation when P1 Absolute Turns Recovery Enable (03.073) = 0. If P1 Absolute Turns Recovery Enable (03.073) = 1 no masking is applied to P1 Rotary Turns Bits (03.033), and so a 16 bit value is always shown.

Parameter | 03.034 P1 Rotary Lines Per Revolution
--- | ---
Short description | Defines the number of rotary lines per revolution for device P1
Mode | RFC‑S
Minimum | 1 | Maximum | 100000
Default | 4096 | Units |
Type | 32 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Rotary Lines Per Revolution (03.034) only has any effect if the position feedback interface is being used with a rotary device (i.e. P1 Linear Feedback Select (03.051) = 0).

P1 Device Type (03.038): AB, AB Servo
P1 Rotary Lines Per Revolution (03.034) should be set to the number of lines per revolution for the encoder connected to the P1 position feedback interface.

P1 Device Type (03.038): FD, FR, FD Servo, FR Servo
P1 Rotary Lines Per Revolution (03.034) should be set to the number of lines per revolution for the encoder connected to the P1 position feedback interface divided by 2.

P1 Device Type (03.038): SC, SC Servo, SC Hiperface, SC EnDat, SC SSI, SC SC, SC BiSS
P1 Rotary Lines Per Revolution (03.034) should be set to the number of sine waves per revolution for the encoder connected to the P1 position feedback interface.

P1 Device Type (03.038): Any other device type
P1 Rotary Lines Per Revolution (03.034) has no effect.

Parameter | 03.035 P1 Comms Bits
--- | ---
Short description | Defines the total number of bits of position information in the comms message from the encoder for device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 48
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Device Type (03.038): SC Hiperface, EnDat, SC EnDat, EnDat 3
Total number of bits of position information in the comms message from the encoder. For consistency with existing devices, even though EnDat 3 devices always transfer 48 position bits regardless of the encoder resolution, this parameter is updated with the number of usable bits of position information provided by the connected EnDat 3 encoder.

P1 Device Type (03.038): SSI, SC.SSI
Total number of bits of position information in the comms message from the encoder including any leading or trailing zeros and the power supply alarm bit if present. The power supply fail detection bit is effectively the LS bit and must be zero to indicate that the power supply is okay. If the number of comms bits is extended to include this bit, the position that is read from the encoder is not affected, but if P1 Error Detection Level (03.040) Bit 2 is set the power supply fail bit will be monitored by the drive and can be used to detect wire break. If the encoder is disconnected the data input is pulled high and triggers a wire break trip. This feature can be used with any SSI encoder where the data is low after the LSB is transmitted by the encoder for at least one clock period.

P1 Device Type (03.038): BiSS, SC BiSS
Total number of bits of position information in the comms message from the encoder excluding the warning and error bits. It is always assumed there is one warning bit and one error bit. The length of the position information includes any zero padding that is included by the encoder. The CRC is applied to the whole message including the error (/E) and warning (/W) bits. The warning bit is ignored, but if the error bit is low then an Encoder 6 trip is initiated.

P1 Device Type (03.038): Any other device type
P1 Comms Bits (03.035) has no effect.

Parameter | 03.036 P1 Supply Voltage
--- | ---
Short description | Defines the supply voltage output for device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | 5V
1 | 8V
2 | 15V

P1 Supply Voltage (03.036) sets the level for the supply voltage output. To ensure that the maximum voltage for the position feedback device is not accidentally exceeded, the device should be disconnected from the drive when the level is being adjusted.

Parameter | 03.037 P1 Comms Baud Rate
--- | ---
Short description | Defines the baud rate used for encoder communications
Mode | RFC‑S
Minimum | 0 | Maximum | 8
Default | 2 | Units | Baud
Type | 8 Bit User Save | Update Rate | Background read, Auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | 100k
1 | 200k
2 | 300k
3 | 400k
4 | 500k
5 | 1M
6 | 1.5M
7 | 2M
8 | 4M

P1 Comms Baud Rate (03.037) defines the baud rate used for encoder communications. Restrictions are applied to the baud rate for different feedback devices, and so the baud rate may be different to the parameter value.

P1 Device Type (03.038): SC.Hiperface
A fixed baud rate of 9600 baud is always used with this type of encoder so P1 Comms Baud Rate (03.037) has no effect.

P1 Device Type (03.038): SC.SSI, SC EnDat, SC BiSS
Any baud rate that is within the range specified for the encoder may be used. The data from the encoder is not used for time critical functions, and so it is recommended that the default value of 300k baud is used unless this needs to be reduced because of a limitation imposed by the encoder.

P1 Device Type (03.038): EnDat, BiSS, SSI, EnDat Alt, BiSS Alt, SSI Alt
Any baud rate that is within the range specified for the encoder may be used. The line delay is measured during initialisation, and used to compensate this delay during communications with the encoder. Therefore there is no timing based restriction on the length of the cable between the position feedback interface and the encoder. However, care should be taken to ensure that the wiring arrangement and the type of cable used are suitable for the selected baud rate and the distance between the position interface and the encoder. See P1 Low Speed Update Rate Active (03.063) for more details on timing restrictions related to the drive sample times.

The drive hardware can malfunction when a BiSS encoder is used and the line delay time is an integral multiple of the clock period. To avoid this problem the drive will automatically increase the baud rate to minimise the effect. This does not affect any parameters, and so the only thing that is visible is that the baud rate is higher than the setting in this parameter. The maximum reduction of the clock period is 62.5ns. For example if 4M Baud is selected the baud rate could be increased up to 5.33M Baud.

P1 Device Type (03.038): EnDat 3
P1 Comms Baud Rate (03.037) has no effect as the drive always uses a 12.5Mbps data rate with these devices.

P1 Device Type (03.038): Any other device
P1 Comms Baud Rate (03.037) has no effect.

Parameter | 03.038 P1 Device Type
--- | ---
Short description | Defines the device type connected to the drive P1 position feedback interface
Mode | RFC‑S
Minimum | 0 | Maximum | 21
Default | 3 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | AB
1 | FD
2 | FR
3 | AB Servo
4 | FD Servo
5 | FR Servo
6 | SC
7 | SC Hiperface
8 | EnDat
9 | SC EnDat
10 | SSI
11 | SC SSI
12 | SC Servo
13 | BiSS
14 | Resolver
15 | SC SC
16 | Commutation Only
17 | SC BiSS
18 | EnDat Alt
19 | SSI Alt
20 | BiSS Alt
21 | EnDat 3

P1 Device Type (03.038) should be set up to match the device connected to the drive P1 position feedback interface. The table below gives the position feedback types supported by the P1 position feedback interface.

P1 Device Type (03.038) | Signals | Position feedback type | Communications
0: AB | Quadrature | Incremental | None
1: FD | Frequency and direction | Incremental | None
2: FR | Forward and reverse | Incremental | None
3: AB Servo | Quadrature and commutation | Absolute commutation signals with incremental | None
4: FD Servo | Frequency and direction, and commutation | Absolute commutation signals with incremental | None
5: FR Servo | Forward and reverse, and commutation | Absolute commutation signals with incremental | None
6: SC | SINCOS | Incremental SINCOS | None
7: SC Hiperface | SINCOS and Hiperface comms | Absolute comms with incremental SINCOS | Hiperface
8: EnDat | EnDat comms | Absolute comms | EnDat 2.1 EnDat 2.2
9: SC EnDat | SINCOS and EnDat comms | Absolute comms with incremental SINCOS | EnDat 2.1
10: SSI | SSI comms | Absolute comms | SSI
11: SC SSI | SINCOS and SSI comms | Absolute comms with incremental SINCOS | SSI
12: SC Servo | SINCOS and commutation | Absolute commutation signals with incremental | None
13: BiSS | BiSS comms | Absolute comms | BiSS
14: Resolver | Resolver | Resolver | None
15: SC SC | SINCOS and single sine and cosine signals per revolution | SINCOS with absolute position from single sine and cosine signals | None
16: Commutation Only | Commutation only | Absolute commutation signals only | None
17: SC BiSS | BiSS comms | Absolute comms with incremental SINCOS | BiSS
18: EnDat Alt | EnDat comms only, but connected to the same comms connections as an SC EnDat device | Absolute comms | EnDat 2.1 EnDat 2.2
19: SSI Alt | SSI comms only, but connected to the same comms connections as an SC SSI device | Absolute comms | SSI
20: BiSS Alt | BiSS comms only, but connected to the same comms connections as an SC BiSS device | Absolute comms | BiSS
21: EnDat 3 | EnDat 3 comms | Absolute comms | EnDat 3

Position feedback type:

Incremental
Position devices that provide incremental feedback do not give absolute position feedback. The position is zero at power-up and accumulates the change of position from that point on. These devices are suitable for motor control in RFC-A mode. They can also be used for RFC-S mode, but some form of phasing auto-tune is required each time the position feedback is initialised.

Absolute commutation signals with incremental
Position devices with commutations signals are intended to provide absolute position feedback for motor control in RFC-S mode. If one of these devices is used for RFC-A mode the commutation signals are ignored. The position information given in P1 Revolution/Pole Pitch Counter (03.028), P1 Position (03.029) and P1 Fine Position (03.030) appears as though the position feedback device is an incremental type in that it is initialised to zero at power-up and then accumulates the change of position from that point on. The commutation signals are used directly by the motor control algorithms in RFC-S mode to determine the motor position after position feedback initialisation. There must be one period of the commutation signals for each pole pair for a rotary motor (i.e. 3 commutation signal periods per revolution for a 6 pole motor), or one period of the commutation signals must be equal to the motor pole pitch for a linear motor. It should be noted that for a movement of up to 1/6 of the commutation signal period after position feedback initialisation the maximum motor torque is limited to 0.866 of the maximum possible torque.

Absolute commutation signals only
Position devices with commutations signals are intended to provide absolute position feedback for motor control in RFC-S mode but can also be used to provide position feedback for motor control in RFC-A mode. The position is derived from the commutation signals alone. A phase locked loop is used to smooth the feedback, but this introduces a delay and there is significant ripple in the position and speed feedback at low speeds. If this method is used for motor control then low speed loop gains should be used and P1 Feedback Filter (03.042) should be used to filter the feedback.

Incremental SINCOS
An incremental SINCOS encoder can be used in the same way as an AB incremental encoder, except that the position resolution is increased with interpolation. These devices are suitable for motor control in RFC-A mode. They can also be used for RFC-S mode, but some form of phasing auto-tune is required each time the position feedback is initialised. The increase in resolution due to interpolation depends on the magnitude and frequency of the sine wave signals at the position feedback interface inputs on the drive. The nominal signal level at the sine wave inputs is 1V peak to peak between the inputs. For example each input could have a 0.5V peak to peak signal, or one input could have no signal and the other a 1V peak to peak signal. If interpolation is not used, the position feedback would have a resolution related to the number of sine waves per revolution (i.e. 512 sine waves per revolution would give position feedback resolution equivalent to a 512 line incremental encoder, which gives 2048 discernible positions per revolution). With the nominal signal level and an input frequency below 5kHz the interpolation using sine waves instead of digital incremental signals increases the resolution by a factor of 65536. For a 512 sine wave encoder this would give a resolution of 512 x 4 x 65536 = 134217728 discernible positions per revolution. The increased resolution due to interpolation is directly proportional to the sine wave signal voltage levels, and also reduces with sine wave signal frequency. The resolution is given by

Resolution = P1 Rotary Lines Per Revolution (03.034) x 4 x 65536 x Vpeak to peak of the sine wave signals x Frequency Factor

where the frequency factor is given below.

1kHz | 5kHz | 50kHz | 100kHz | 200kHz | 500kHz
1.00 | 1.00 | 0.86 | 0.66 | 0.39 | 0.14

Increasing the sine wave signal level above 1V peak to peak may increase the resolution if it has been reduced due to frequency, but the level should not be increased above 1.5V or else the input will saturate and the sine waves will be distorted.

It should be noted that there is likely to be some electrical noise on the sine wave signals at the drive input and further noise added within the drive. One reason to use sine wave interpolation is to reduce the acoustic noise produced by the motor especially when high controller gains are used. The electrical noise on the sine wave signals will limit the extent to which the motor acoustic noise can be reduced.

Absolute comms with incremental SINCOS
The absolute position is obtained after position feedback initialisation via the comms interface and then after that point by tracking the incremental change from the sine wave signals. Interpolation is used to increase the position resolution. The comms interface can be used to check the position derived from the sine waves. It can also be used for bi-direction transfer of data between the drive and encoder (except SSI comms). These devices can be used for motor control in RFC-A or RFC-S modes.

Absolute comms
The absolute position is obtained at all times via the encoder comms. The comms interface can also be used for bi-directional transfer of data between the drive and the encoder (except SSI mode). These devices can be used for motor control in RFC-A or RFC-S modes.

Resolver
A resolver can be used to provide absolute position feedback within the range covered by one electrical revolution of the resolver (i.e. 360° mechanical for a 2 pole device, 180° mechanical for a 4 pole device, etc.). An angle of 0 degrees corresponds to the position where the cosine input is at its maximum and in phase with the excitation and the sine input zero. A resolver can be used for motor control in RFC-A mode or RFC-S mode. In RFC-S mode a 2 pole resolver can be used with a motor with any number of motor poles, but with any other number of poles there must be an integer number of motor poles for each resolver pole. In RFC-A mode this restriction does not apply. Standard or high speed sampling can be selected with P1 Resolver Excitation (03.066). If standard sampling is selected and the position feedback used for motor control the maximum operating speed is limited before the control performance starts to deteriorate. See P1 Resolver Excitation (03.066) for more details.

SINCOS with absolute position from sine and cosine signals
This type of device is intended to provide absolute position feedback for motor control in RFC-S mode. The feedback from the encoder consists of sine and cosine signals giving one cycle per revolution to determine the absolute position, and sine and cosine signals giving P1 Rotary Lines Per Revolution (03.034) cycles per revolution to provide more accurate position feedback that is used after the initial position has been obtained from the single cycle signals. To improve the accuracy of the absolute position a marker signal may also be provided that adjusts the absolute position when the encoder rotates through the marker for the first time. If a marker signal is not available or is not connected, then it is possible to disable this feature. See P1 Marker Mode (03.031) for more details. The position information given in P1 Position (03.029) and P1 Fine Position (03.030) is initialised to the position within one turn and P1 Revolution/Pole Pitch Counter (03.028) is set to zero when the device is initialised based on the single cycle signals. These are then adjusted if the marker is being used when the first marker is detected. This type of device can also be used in RFC-A mode if required.

Care should be taken to ensure that the position feedback device is connected correctly. For example a Heidenhain ERN1387 device should be connected as follows: 1/2=A+/A-(Cosine), 3/4=B+/B-(Sine), 5/6=R+/R-(Marker), 7/8=C+/C-(Single turn cosine), 9/10=D+/D-(Single turn sine). It is assumed that the marker occurs at the positive zero crossing of the single turn cosine signal when operating in the forwards direction (i.e. compatible with the ERN1387). To ensure the drive can correctly detect the reference marker pulse with a Heidenhain ERN1387 encoder it is recommended that bit 3 of P1 Marker Mode (03.031) is set to 1.

This type of encoder uses analogue sine wave signals and a low level marker signal. It is particularly important that good wiring practice is used or else spurious wire break detection or incorrect absolute position measurement can occur.

Communications:

Hiperface
Hiperface is an asynchronous bi-direction communications protocol that is only used with incremental sine waves. Therefore it can be used to check the position derived from the sine waves or for bi-direction transfer of data between the drive and encoder. A checksum is provided for error checking.

EnDat 2.1
EnDat 2.1 is a synchronous bi-direction communications protocol that is intended to be used with incremental sine waves. Therefore it can be used to check the position derived from the sine waves or for bi-direction transfer of data between the drive and encoder. It can be used as an absolute comms only type position feedback interface, but the resolution of the position feedback using this method may be limited. If it is used in this way it is not possible to use the position feedback via comms at the same time as communicating with the encoder for data transfer or electronic nameplate. A CRC is provided for error checking.

EnDat 2.2 and BiSS C Mode
EnDat 2.2 and BiSS are synchronous bi-direction communications protocols that are intended to be used alone. It is possible to obtain position feedback at the same time as communicating with the encoder for data transfer or electronic nameplate. A CRC is provided for error checking.

EnDat 3
EnDat 3 is a asynchronous bi-direction communications protocol. This uses balanced line communications so that both the encoder power supply and communication signals can be sent over the same 2-wires. It is possible to obtain position feedback at the same time as communicating with the encoder for data transfer or electronic nameplate. A CRC is provided for error checking.

SSI
SSI is a uni-directional communications protocol that is intended to be used alone. It is only possible to obtain the position information from the encoder and it is not possible to transfer data between the drive and the encoder. No error checking is provided by the SSI protocol, and so encoders based on this interface are not recommended for new applications.

Parameter | 03.039 P1 Termination Select
--- | ---
Short description | Used to enable or disable the terminations on the position feedback interface inputs
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default | 1 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Termination Select (03.039) is used to enable or disable the terminations on the position feedback interface inputs. The function of P1 Termination Select (03.039) depends on the position feedback device type selected in P1 Device Type (03.038) as shown below.

Terminals 5/6 have selectable pull-apart resistors which follow the same state as the termination resistors for terminals 5/6, unless described differently below.

P1 Device Type (03.038): AB, FD, FR, AB Servo, FD Servo, FR Servo

Terminal | Input | 03.039 = 0 | 03.039 = 1 | 03.039 = 2
1/2 & 3/4 | A1 & B1 | Disabled | Enabled | Enabled
5/6 | Z1 | Disabled | Disabled | Enabled

U1, V1 & W1 terminations (terminals 7/8, 9/10 & 11/12) are always enabled for AB Servo, FD Servo and FR Servo encoders.

P1 Device Type (03.038): SC, SC Servo, SC SC

Terminal | Input | 03.039 = 0 | 03.039 = 1 | 03.039 = 2
1/2 & 3/4 | Cos1 & Sin1 | Disabled | Enabled | Enabled
5/6 | Z1 | Disabled | Disabled | Enabled

U1, V1 & W1 (terminals 7/8, 9/10 & 11/12) terminations are always enabled for SC Servo encoders. SCs1 and SSn1 (terminals 7/8 & 9/10) terminations are always enabled for SC SC encoders.

P1 Device Type (03.038): SC Hiperface, SC EnDat, SC SSI, SC BiSS

Terminal | Input | 03.039 = 0 | 03.039 = 1 | 03.039 = 2
1/2 & 3/4 | Cos1 & Sin1 | Disabled | Enabled | Enabled
5/6 | D1 | Enabled | Enabled | Enabled

For SC EnDat and SC SSI encoder the pull-apart resistors on the D1 input/output (terminals 5/6) are always disabled, and for SC Hiperface encoders the pull-apart resistors on the D1 input/output (terminals 5/6) are always enabled.

P1 Device Type (03.038): EnDat, BiSS, SSI

Terminal | Input | 03.039 = 0 | 03.039 = 1 | 03.039 = 2
1/2 & 3/4 | D1/CLK1 | Enabled | Enabled | Enabled
5/6 | Z1 | Disabled | Disabled | Enabled

If the P2 Device type (03.138) is set to EnDat, BiSS or SSI and the encoder simulation output is enabled, then the Z1 input becomes the data (D2) input for the P2 position interface and termination resistors are always enabled and pull-apart resistors are always disabled.

P1 Device Type (03.038): Resolver, EnDat 3
P1 Termination Select (03.039) has no effect as the termination and pull-apart resistors are always disabled. For EnDat 3 the terminations must be provided externally on an interface board.

P1 Device Type (03.038): Commutation Only
P1 Termination Select (03.039) has no effect as terminations are always enabled.

Parameter | 03.040 P1 Error Detection Level
--- | ---
Short description | Used to enable or disable position feedback trip functions
Mode | RFC‑S
Minimum | 0 (Display: 00000000) | Maximum | 255 (Display: 11111111)
Default | 1 (Display: 00000001) | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Binary | Decimal Places | 0
Coding | RW, BU

This parameter can be used to enable or disable position feedback trip functions as follows:

Bit | Function | Trip(s) | Comments
0 | Enable wire break detection. | Encoder 2 | Bits 5 to 7 have no effect if this bit is set to zero.
1 | Enable phase error detection. | Encoder 3 |
2 | Enable SSI power supply alarm bit monitor. | Encoder 6 |
3 | Disable indicated trips. | Encoder 1 to Encoder 6 | Trips related to bits 0, 1, 2, 5, 6 and 7 do not occur if this bit is set to one. See note below about the position feedback device becoming uninitialised.
4 | Disable indicated trip. | Encoder 7 |
5 | Enable wire break detection for sine wave commutation signals for SC SC type encoders. | Encoder 2 | This wire break detection does not operate until initialisation of the position feedback device is complete. If a marker signal is being used to improve the absolute accuracy of the feedback (P1 Marker Mode (03.031) Bit 4 = 0), then this is after the first marker has been detected. It is important therefore, to set P1 Marker Mode (03.031) Bit 4 = 1 if a marker is not being used.
6 | Enable wire break detection for the marker with SC SC type encoders with Heidenhain ERN1387 type marker signals. | Encoder 2 |
7 | Enable more sensitive resolver wire break detection. | Encoder 2 | The standard wire break detection is only likely to detect a break in the excitation signal, or both the sine and cosine signals together. The more sensitive system will detect a break in any signal provided the motor is rotating. If the motor is stationary, there are positions where wire break will not be detected. The standard system uses 10% of the expected 1Vrms feedback signals as the detection threshold, but the more sensitive system uses 80%. If the resolver ratio is significantly less than 3:1 with 3V excitation, or 2:1 with 2V excitation, then the more sensitive detection system should not be used.

Bits 3 and 4 do not prevent the device from becoming un-initialised. The trip is suppressed, but the device is still un-initialised and this is indicated by the appropriate bit for the position feedback interface in Position Feedback Initialized (03.076).

Encoder trips
The following table shows trips that can be initiated that are related to the position feedback interface P1. The sub-trip number is 1 for the drive P1 position feedback interface.

Drive trip | Encoders | Reason for error
Encoder 1 | All | Power supply short circuit
Encoder 2 | AB, FD, FR, AB Servo, FD Servo, FR Servo | Hardware wire-break detect on A1, B1 and Z1 inputs 1. (Note that there is no wire break detection on the U1, V1 and W1 commutation inputs.)
SC, SC Servo, SC Hiperface, SC EnDat, SC SSI, Resolver, SC SC, SC BiSS | Software wire break detection on sine wave signals. Marker and single turn sine wave commutation signal wire break detection for SC SC devices5. (Note that there is no wire break detection on the U1, V1 and W1 commutation inputs.)
Encoder 3 | AB Servo, FD Servo, FR Servo, SC Servo | Phase error 2
SC Hiperface, SC EnDat, SC SSI, SC BiSS | Sine/cosine phase error 3
Encoder 4 | SC Hiperface, SC EnDat, EnDat, BISS, SC BiSS, EnDat 3 | Comms timeout
Encoder 5 | SC Hiperface, SC EnDat, EnDat, BISS, SC BiSS, EnDat 3 | Checksum/CRC error
SC SSI, SSI | Not ready at start of position transfer (i.e. data input not one)
Encoder 6 | SC Hiperface, SC EnDat, EnDat, BiSS, SC BiSS, EnDat 3 | The encoder has indicated an error
SSI, SC SSI | Power supply alarm bit active
Encoder 7 | All | A set-up parameter for the device, or the number of pole pairs when used in the position feedback set-up, for the currently selected motor have been changed. (The number of poles is only used in the set-up for AB Servo, FD Servo, FR Servo, SC Servo and Commutation Only devices).
Encoder 8 | EnDat, SSI, BiSS | P1 Device Type (03.038), P1 Comms Bits (03.035), P1 Comms Baud Rate (03.037), P1 Calculation Time (03.060), P1 Recovery Time (03.061), P1 Line Delay Time (03.062) and P1 User Comms Enable (03.067) are used to determine the time taken for the communications exchange with the encoder. If this time exceeds 250μs an Encoder 8 trip is initiated.
Encoder 9 | All | Speed feedback selected from an option slot that does not have a position feedback category option module fitted
Phasing Error | All | Incorrect encoder phasing 4
Encoder 11 | EnDat 3 | The control board hardware does not support the selected device type.
Encoder 12 | SC Hiperface, BiSS, EnDat 3 | The encoder could not be identified during auto-configuration or the identified encoder type is not supported by the drive (i.e. linear encoder is detected but not supported). For EnDat 3 this trip may be triggered on a supported encoder if the encoder memory cannot be accessed during initialisation.
Encoder 13 | SC Hiperface, SC EnDat, EnDat, BiSS, SC BiSS, EnDat 3 | Data read from the position feedback device during auto-configuration is out of range
Encoder 14 | BiSS, SC BiSS | The turns or position padding values in parameter P1 Additional Configuration (03.074) are out of range.

1. If the terminations are not enabled on the A1, B1 or Z1 inputs the wire break system will not operate. (Note that as default the Z1 input terminations are disabled to disable wire break detection on this input.)
2. Phase error detection for AB Servo, FD Servo, FR Servo or SC Servo encoders monitors the relationship between the position from the incremental signals and the commutation signals to ensure that the incremental pulses have been counted correctly. The error is detected if the incremental position moves outside the position range defined by the UVW commutation signals by 10o. The trip is initiated if the error is detected for 10 consecutive samples. This system should not be used unless one encoder line (AB Servo), or two lines (FD Servo, FR Servo), are less than 10° electrical or else spurious Encoder 3 trips will occur.
3. Phase error detection for SINCOS encoders with comms monitors the relationship between the position derived from the sine waves with the position derived via comms. The encoder is interrogated via comms and the comparison is made once per second. If the error is greater than 10° electrical for 10 consecutive samples the trip is initiated. This system should not be used unless one sine wave is less than 10° electrical or else spurious Encoder 3 trips will occur.
4. Incorrect encoder phasing is detected if the motor reaches half of the speed defined by VM_SPEED_FREQ_REF[MAX] and the phasing error is large enough for the motor to accelerate uncontrollably.
5. Detection of wire break on the sine wave commutation signals or marker of an SC SC device requires the encoder to rotate before the fault is detected, i.e. up to 1 turn for the sine wave commutation signals and up to 3 turns for the marker).

Wire-break detection
It may be important to detect a break in the connections between the drive and the position feedback device. This feature is provided for most position feedback devices either directly or indirectly as listed below.

Device | Detection method | Trip produced
AB, FD, FR, AB Servo, FD Servo, FR Servo | Hardware detectors on the A1, B1 and Z1 signal detect a wire break. | Encoder 2
SC, SC Servo, SC Hiperface, SC EnDat, SC SSI, SC SC, SC BiSS | The magnitudes of the sine wave signals are monitored as the magnitude of a vector which is calculated as √(Sine2+Cosine2). If this is less than the value produced by two valid waveforms with a peak to peak magnitude of 0.25V (i.e. 0.25 of the nominal level of 1V peak to peak) then a trip is initiated. This always detects wire break in the sine and cosine connections if the position feedback is changing. If the position feedback is stationary this may not detect wire break until the position feedback moves, e.g. if the sine connection is broken, but the cosine is at it's maximum then wirebreak will not be detected. Additional monitoring is provided for SC SC encoders to give software wire break detection for the single turn sine wave commutation signals and the marker. If the device is a Heidenhain ERN1387 the marker is too small for hardware wire break detection, and so the additional software detection is required to detect wire break on the marker. This additional detection can be enabled with bits 5 and 6 of P1 Error Detection Level (03.040). | Encoder 2
Resolver | The magnitudes of the sine and cosine input signals are monitored in a similar way to SINCOS signals where the peak of the sine and cosine waveforms are used to calculate the vector magnitude. If the calculated value is less than the value produced by two valid waveforms with a differential peak to peak magnitude of 0.4V then a trip is initiated. This detects wire break in the sine and cosine connections. If the position feedback is stationary this may not detect wire break until the position feedback moves, e.g. if the sine connection is broken, but the cosine is at it's maximum then wire break will not be detected. | Encoder 2
SC Hiperface, SC EnDat, EnDat, BiSS, SC BiSS, EnDat 3 | Wire break in the comms link is detected by a CRC or timeout error. Due to the timing of the BiSS interface it is likely that an Encoder 5 (CRC error) or Encoder 6 (the encoder has detected an error) are more likely to occur than an Encoder 4 (Comms timeout) if the encoder is not connected or does not respond. | Encoder 4, Encoder 5
SSI, SC SSI | Wire break detection in the comms is difficult with these devices. However, if power supply alarm bit monitoring is enabled the drive will be looking for a one at the start of the message and a zero to indicate that the power supply is okay. If the clock stops or the data line is disconnected the data input to the drive may stay in one state or the other and cause a trip. | Encoder 5, Encoder 6

Position feedback power supply trips
The position feedback power supply from the drive can be switched off by the drive either because the power supply is overloaded (Encoder 1 trip) or because the internal 24V supply within the drive is overloaded (PSU 24V trip). The internal 24V supply provides power for the position feedback power supply, user 24V output, digital I/O, option modules etc. To ensure that an Encoder 1 trip is not initiated when the internal 24V is overloaded, and subsequently switched off by the drive, there is a delay of 40ms in the detection of Encoder 1 trip. It is possible for other position feedback trips, such as wire break detection (i.e. Encoder 2), to occur when the power supply is removed from the position feedback device. Therefore overloading the internal 24V supply or the position feedback supply could result in an immediate Encoder 2 trip. To ensure that the correct reason for the trip is given PSU 24V and Encoder 1 trips override an existing Encoder 2 to Encoder 6 trip. This means that both the original trip (Encoder 2 to Encoder 6) and then the new trip (PSU 24V or Encoder 1) are stored in the trip log.

Parameter | 03.041 P1 Auto-configuration Select
--- | ---
Short description | Set to 1 to enable interrogation of the encoder to determine the set up required
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 1 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Disabled
1 | Enabled

P1 Device Type (03.038): SC Hiperface, SC EnDat, EnDat, EnDat Alt
If auto-configuration is enabled (i.e. P1 Auto-configuration Select (03.041) = 1) then during position feedback initialisation the encoder is interrogated to determine whether the encoder is a rotary or linear encoder and P1 Linear Feedback Select (03.051) is set up appropriately. Then the following parameters are set up based on information from the encoder:

Rotary | Linear
P1 Rotary Turns Bits (03.033) | P1 Linear Comms Pitch (03.052)
P1 Rotary Lines Per Revolution (03.034) | P1 Linear Line Pitch (03.053)
P1 Comms Bits (03.035) | P1 Comms Bits (03.035)
P1 Additional Configuration (03.074) | P1 Linear Comms And Line Pitch Units (03.054)

The following actions are also taken to set up the timing for the encoder.

Comms Protocol | Actions taken
EnDat 2.1 | P1 Calculation Time (03.060) = From the encoder P1 Recovery Time (03.061) = 30μs Line delay measured and result written to P1 Line Delay Time (03.062)
EnDat 2.2 | P1 Calculation Time (03.060) = From the encoder P1 Recovery Time (03.061) is set to 4μs (and the encoder itself is set up to use its short recovery time of 3.75μs) if the P1 Comms Baud Rate (03.037) is 1.5M or more. Line delay measured and result written to P1 Line Delay Time (03.062)

Once these parameters have been set up it should be possible for the drive to operate correctly with the encoder. Auto-configuration occurs as part of the position interface initialisation if selected, and so if the auto-configuration fails (i.e. communications cannot be established) then initialisation will not be completed. If initialisation has not been completed successfully the drive cannot be enabled (see Enable Conditions (06.010)). For SC Hiperface encoders the drive must identify the encoder model number to perform auto-configuration. If communications is established, but the drive cannot recognise the encoder model, an Encoder 12 trip is produced immediately.

If auto-configuration is disabled ((i.e. P1 Auto-configuration Select (03.041) = 0) then none of the above actions are carried out except for the line delay measurement.

P1 Device Type (03.038): EnDat 3
No user configuration is required for EnDat 3 as the same baud-rate and position alignment is used for all EnDat 3 encoders. These devices always auto-configure themselves, therefore this parameter has no effect and the following parameters will be always be updated with data stored during a successful initialisation. These parameters are not used to establish comms with the encoder, they are just provided for indication:

Parameter
P1 Rotary Turns Bits (03.033)
P1 Comms Bits (03.035)
P1 Calculation Time (03.060)

P1 Device Type (03.038): BiSS, SC BiSS, BiSS Alt
If auto-configuration is enabled (i.e. P1 Auto-configuration Select (03.041) = 1) then during position feedback initialisation the standard CRC for BiSS encoders (X6+X+1) is automatically selected by setting P1 Additional Configuration (03.074) to 67000000 and the maximum baud rate is automatically selected by setting P1 Comms Baud Rate (03.037) to 4MBaud. All BiSS encoders should operate with a clock frequency of 10MHz, and so this should be suitable for all devices. If the encoder contains a BP3 type EDS (electronic data sheet) as defined in the BiSS specifications then the drive will attempt to use this to set up parameters to allow the encoder to function. For this to work correctly the EDS-bank (Bank 0 Address 65) must be set to the bank containing the start of the EDS (i.e. the common part EDS), Profile ID Byte 1 (Bank 0 Addresses 66) must be define the BP3 profile (i.e. the MS 4 bits are 6) and Profile ID Byte 0 (Bank 0 Address 67) must define the total number of communication bits. The EDS is only used for rotary encoders, and so P1 Linear Feedback Select (03.051) must be zero. The following data from the encoder is used.

Bank | Address | Data | Comments | Action on failure
0 | 66 | Profile-ID Byte 1 | This must define a BP3 profile and so the MS 4 bits must be 6. Bit 0 contains the "C" Bit which is 1 if the CRC bits are included in communications bits defined in Profile-ID Byte 0 or zero if not. | The EDS data is not used.
0 | 67 | Profile-ID Byte 0 | If C Bit in Profile-ID Byte 1 = 1 Total number of communications bits = P1 Comms Bits (03.035) + Error Bit + Warning Bit + 6 CRC Bits. If C Bit in Profile-ID Byte 1 = 0 Total number of communications bits = P1 Comms Bits (03.035) + Error Bit + Warning Bit. | If the calculated value for P1 Comms Bits (03.035) is less than 0 or greater than 48 an Encoder 13.15 trip is initiated.
0 | 65 | EDS-Bank | Used to locate the start of the common part of the EDS. |
EDS-Bank | 12 | TBUSY_S | Gives the encoder calculation time in 250ns units. This is converted to microseconds and written to P1 Calculation Time (03.060) | If the calculated value is larger than 20us an Encoder 13.16 trip is initiated.
EDS-Bank + 1 | 8 | EN_TYP | This must be zero indicating a rotary encoder. | If the value is not zero an Encoder 12.1 trip is initiated.
EDS-Bank + 1 | 10 | MT_LEN | This is the number of encoder turns bits and is written to P1 Rotary Turns Bits (03.033). | If the value is larger than 16 an Encoder 13.14 trip is initiated.
EDS-Bank + 1 | 20 | SIP_CNT Byte 3 | These 4 bytes form a 32 bit value that defines the number of signals per revolution for an SC.BiSS encoders and are written to P1 Rotary Lines Per Revolution (03.034). | If the value is larger than 100000 an Encoder 13.11 trip is initiated.
EDS-Bank + 1 | 21 | SIP_CNT Byte 2 |  |
EDS-Bank + 1 | 22 | SIP_CNT Byte 1 |  |
EDS-Bank + 1 | 23 | SIP_CNT Byte 0 |  |

Once the auto-configuration data has been obtained successfully P1 Recovery Time (03.061) is set to 13us, which is the longest timeout used by any BiSS encoders, and then line delay measurement is carried out to set up P1 Line Delay Time (03.062).

If auto-configuration is disabled (i.e. P1 Auto-configuration Select (03.041) = Disabled (0)) then none of the above actions are carried out except for the line delay measurement.

Some BiSS encoders only support unidirectional communications and the drive will trip Encoder 4 when attempting to intiailise one of these encoders with P1 Auto-configuration Select (03.041) = Enabled (1). If a unidirectional BiSS encoder is used then P1 Auto-configuration Select (03.041) must be set to Disabled (0) and the encoder parameters manually configured.

P1 Device Type (03.038): All other device types
P1 Auto-configuration Select (03.041) has no effect.

Parameter | 03.042 P1 Feedback Filter
--- | ---
Short description | Defines the time period for a sliding window filter that may be applied to the feedback taken from the drive P1 position feedback interface
Mode | RFC‑S
Minimum | 0 | Maximum | 5
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Disabled
1 | 1ms
2 | 2ms
3 | 4ms
4 | 8ms
5 | 16ms

P1 Feedback Filter (03.042) defines the time period for a sliding window filter that may be applied to the feedback taken from the drive P1 position feedback interface. This is particularly useful in applications where the drive encoder is used to give speed feedback for the speed controller and where the load includes a high inertia, and so the speed controller gains are very high. Under these conditions, without a filter on the feedback, it is possible for the speed loop output to change constantly from one current limit to the other and lock the integral term of the speed controller. In Unidrive SP this filter was applied to the output of the sensorless speed feedback, however, a separate filter is now provided (see Sensorless Mode Filter (03.079)).

Parameter | 03.043 P1 Maximum Reference
--- | ---
Short description | Defines the maximum speed reference from device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 33000
Default | 3000 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

The speed feedback from the drive P1 position feedback interface can be used as a source to control a parameter. The speed feedback is scaled to give a value as a percentage of P1 Maximum Reference (03.043) in 0.1% units which is displayed in P1 Reference (03.045). The value is then scaled by the P1 Reference Scaling (03.044) and then routed to the destination defined by P1 Reference destination (03.046).

Normally the destination is updated every 4ms, but if the destination is the Hard Speed Reference (03.022), P1 Maximum Reference (03.043) = VM_SPEED_FREQ_REF[MAX] and P1 Reference Scaling (03.044) = 1.000 it is updated every 250μs. Although the hard speed reference is updated every 250μs internally a value in rpm or mm/s is written to Hard Speed Reference (03.022) every 4ms for indication only. It should be noted that if the fast update method is used the resolution of the speed feedback devived from the position feedback device defines the resolution of the hard speed reference and that any ripple on the feedback will be present on the hard speed reference (see Speed Feedback (03.002)).

Parameter | 03.044 P1 Reference Scaling
--- | ---
Short description | Defines the scaling applied to P1 reference
Mode | RFC‑S
Minimum | 0.000 | Maximum | 4.000
Default | 1.000 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW

See P1 Maximum Reference (03.043).

Parameter | 03.045 P1 Reference
--- | ---
Short description | Displays the value in P1 reference
Mode | RFC‑S
Minimum | -100.0 | Maximum | 100.0
Default |  | Units | %
Type | 16 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, ND, NC, PT

See P1 Maximum Reference (03.043).

Parameter | 03.046 P1 Reference destination
--- | ---
Short description | Defines the destination parameter for P1 reference
Mode | RFC‑S
Minimum | 0.000 | Maximum | 59.999
Default | 0.000 | Units |
Type | 16 Bit User Save | Update Rate | Drive reset read
Display Format | Menu Param Numeric | Decimal Places | 3
Coding | RW, DE, PT, BU

See P1 Maximum Reference (03.043).

Parameter | 03.047 P1 SSI Incremental Mode
--- | ---
Short description | Set to 1 to enable SSI incremental mode
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Device Type (03.038): EnDat, BISS, EnDat 3
P1 SSI Incremental Mode (03.047) has no effect and these comms modes can only operate in incremental mode, i.e. the absolute position is taken during encoder initialisation and then incremental positions are accumulated from that point on, to determine the position. If there is an error in the position read from the encoder this will be detected from the CRC check, and the position data will be ignored until correct data is available or the drive trips after a number of consecutive errors. This prevents large spurious changes in position due to data errors, and so absolute mode is not required.

P1 Device Type (03.038): SSI
If P1 SSI Incremental Mode (03.047) = 0 the complete absolute position is read at each sample. Care should be taken when using this mode as some unwanted effects can occur when the encoder passes through the boundary between its maximum position and zero. In this mode the encoder can be used for motor control provided at least 6 bits of turns information are provided by the encoder otherwise an over speed trip will be produced as the position passes over the maximum position to zero boundary. P1 Normalised Position (03.058) can be used for position control over this boundary provided the normalised turns bits are set up so that the normalised positions do not contain turns information that is not available from the encoder. As the SSI format does not include any error checking it is not possible to detect if the position data has been corrupted by noise. The benefit of using the absolute position directly from an SSI encoder is that even if the encoder communications are disturbed by noise and position errors occur, the position will always recover the correct position after the disturbance has ended.

If P1 SSI Incremental Mode (03.047) = 1 the absolute position is only taken from the encoder during initialisation. The change of position over each sample is then accumulated to determine the position. This method always gives 16 bits of turns information that can always be used without jumps in position whatever value is used as the turns bits for normalisation. If noise corrupts the data from an SSI encoder it is possible to have apparent large change of position, and this can result in the turns information becoming and remaining corrupted until the encoder is re-initialised.

If an SSI encoder is used, but is not powered from the drive, and the encoder is powered up after the drive, it is possible that the first change of position detected could be large enough to cause the problems described above. This can be avoided if the encoder interface is initialised with Initialise Position Feedback (03.075) after the encoder has powered up. If the encoder includes a power supply alarm bit, the power supply monitor should be enabled. This will ensure that the drive remains tripped until the encoder is powered up and the action of resetting the trip will reinitialise the encoder interface.

P1 Device Type (03.038): All other device types
P1 SSI Incremental Mode (03.047) has no effect.

Parameter | 03.048 P1 SSI Binary Mode
--- | ---
Short description | Set to 1 to enable SSI binary mode
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Device Type (03.038): SC SSI, SSI
SSI encoders normally use Gray code data format. However, some encoders use binary format which may be selected by setting P1 SSI Binary Mode (03.048) to one.

P1 Device Type (03.038): All other device types
P1 SSI Binary Mode (03.048) has no effect.

Parameter | 03.049 P1 Additional Power-up Delay
--- | ---
Short description | Defines an additional delay for when any attempt is made to communicate to the device P1
Mode | RFC‑S
Minimum | 0.0 | Maximum | 25.0
Default | 0.0 | Units | s
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW, BU

P1 Device Type (03.038): EnDat 3
EnDat 3 does not require a minimum delay before an attempt to communicate with a device, as it simply will not respond until it is stable and ready. The maximum time specified by the manufacturer for an encoder to be ready after power-up is 4s. Therefore, during the discovery stage the drive will attempt to establish communications for up to 4s before a communications timeout trip is reported on the drive. If an encoder responds earlier than the 4s maximum, then once enough consecutive valid responses have been received, the drive will leave the discovery stage and start the final initialisation steps. As an additional power-up delay is not required for EnDat 3 devices, the value in this parameter is not used.

P1 Device Type (03.038): Any other device
When the position feedback is initialised, at power-up or at any other time, a delay is included before the information from the feedback device is used or any attempt is made to communicate with the device. The minimum delays are shown in the table below. P1 Additional Power-up Delay (03.049) defines an additional delay that is added to the minimum delay.

P1 Device Type (03.038) | Minimum delay
AB, FD, FR AB Servo, FD Servo, FR Servo SC, SC Servo Resolver, SC SC | 100ms
SC Hiperface | 150ms
EnDat, SC EnDat SSI, SC SSI BISS, SC BiSS | 1.3s

Parameter | 03.050 P1 Feedback Lock
--- | ---
Short description | Set to 1 to prevent the position feedback parameters for P1 being updated
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

If P1 Feedback Lock (03.050) = 1 then P1 Revolution/Pole Pitch Counter (03.028), P1 Position (03.029) and P1 Fine Position (03.030) are not updated. If P1 Feedback Lock (03.050) = 0 then these parameters are updated normally.

Parameter | 03.051 P1 Linear Feedback Select
--- | ---
Short description | Set to 1 to configure the P1 interface to operate with a linear position feedback device
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read, Auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

If P1 Linear Feedback Select (03.051) = 0 then the drive P1 position feedback interface is configured to operate with a rotary position feedback device. P1 Rotary Turns Bits (03.033) and P1 Rotary Lines Per Revolution (03.034) should be used to set up the position feedback interface.

If P1 Linear Feedback Select (03.051) = 1 then the position feedback interface is configured to operate with a linear position feedback device. P1 Linear Comms Pitch (03.052) and P1 Linear Line Pitch (03.053) should be used to set up the position feedback interface.
Note: Linear feedback devices are not supported currently over EnDat 3, as the implementation is designed for 2-wire rotary encoders.

Parameter | 03.052 P1 Linear Comms Pitch
--- | ---
Short description | Defines the distance covered by the least significant bit of the position information in a comms message from a linear encoder
Mode | RFC‑S
Minimum | 0.001 | Maximum | 100.000
Default | 0.001 | Units |
Type | 32 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 3
Coding | RW

P1 Device Type (03.038): SC Hiperface, EnDat, SC EnDat, SSI, SC SSI, BiSS, SC BiSS
P1 Linear Comms Pitch (03.052) is used to define the distance covered by the least significant bit of the position information in a comms message from a linear encoder. The units used by this parameter are defined by P1 Linear Comms And Line Pitch Units (03.054).

P1 Device Type (03.038): Any other device
P1 Linear Comms Pitch (03.052) has no effect.

Parameter | 03.053 P1 Linear Line Pitch
--- | ---
Short description | Defines the linear line pitch for device P1
Mode | RFC‑S
Minimum | 0.001 | Maximum | 100.000
Default | 0.001 | Units |
Type | 32 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 3
Coding | RW

P1 Linear Line Pitch (03.053) only has any effect if the position feedback interface is being used with a linear device (i.e. P1 Linear Feedback Select (03.051) = 1) and should be used to define the distances listed below for each type of device. The units used by this parameter are defined by P1 Linear Comms And Line Pitch Units (03.054).

P1 Device Type (03.038): AB, AB Servo
P1 Linear Line Pitch (03.053) should be set to the distance covered by one line period on the encoder.

P1 Device Type (03.038): FD, FR, FD Servo, FR Servo
P1 Linear Line Pitch (03.053) should be set to the distance covered by two line periods on the encoder.

P1 Device Type (03.038): SC, SC Hiperface, SC EnDat, SC SSI, SC Servo, SC BiSS
P1 Linear Line Pitch (03.053) should be set to the distance covered by one sine wave period on the encoder.

P1 Device Type (03.038): SC SC
P1 Linear Line Pitch (03.053) should be set to the distance covered by one sine wave period of the incremental sincos signals on the encoder.

P1 Device Type (03.038): Resolver
P1 Linear Line Pitch (03.053) should be set to the distance covered by one pole of the resolver divided by 214.

P1 Device Type (03.038): Any other device
P1 Linear Line Pitch (03.053) has no effect.

Parameter | 03.054 P1 Linear Comms And Line Pitch Units
--- | ---
Short description | Defines the linear units in either millimetres or micrometres
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | millimetres
1 | micrometres

P1 Linear Comms And Line Pitch Units (03.054) defines the units used by P1 Linear Comms Pitch (03.052) and P1 Linear Line Pitch (03.053) in either millimetres or micrometres.

Parameter | 03.055 P1 Pole Pair Pitch
--- | ---
Short description | Defines the change of position for one electrical revolution of the drive output with a linear position device.
Mode | RFC‑S
Minimum | 0.01 | Maximum | 1000.00
Default | 10.00 | Units | mm
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 2
Coding | RW

P1 Pole Pair Pitch (03.055) gives the distance equivalent to one electrical revolution when linear position feedback is used with a motor. One electrical revolution is one cycle of the a.c. output current from the drive. If the linear position feedback device is being used with a linear motor, then P1 Pole Pair Pitch (03.055) should be set to the pole pair pitch of the motor. The pole pitch for linear motors can be the distance between the pole pieces on the stator as shown below. If this is the case the the pole pair pitch is twice the length of the motor pole pitch. If Number Of Motor Poles (05.011) is set up correctly for a linear motor as 2, then the position feedback as shown in P1 Position (03.029) should change by one revolution (65536) over the distance defined by P1 Pole Pair Pitch (03.055).

If the linear position feedback is not being used with a motor then the pole pair pitch is the distance over which the position feedback as shown in P1 Position (03.029) should change by one revolution, i.e. 65536.

Parameter | 03.056 P1 Feedback Reverse
--- | ---
Short description | Set to 1 to reverse the direction of the position feedback
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

If P1 Feedback Reverse (03.056) = 1 the position feedback is negated. This can be used to reverse the direction of the position feedback. It should be noted that the position and the turns are negated, so for example if P1 Revolution/Pole Pitch Counter (03.028) = 0 and P1 Position (03.029) = 1000 with P1 Feedback Reverse (03.056) = 0, then if P1 Feedback Reverse (03.056) is set to one then P1 Revolution/Pole Pitch Counter (03.028) = 65535 (-1) and P1 Position (03.029) = 64536 (65536 - 1000). This will have an effect on the initial position for example, for a resolver which is a single turn absolute device, where the initial P1 Revolution/Pole Pitch Counter (03.028) = 0 with P1 Feedback Reverse (03.056) = 0 or 65535 (-1) with P1 Feedback Reverse (03.056) = 1.

Reversing the position feedback will not compensate for the following situations:

1. The direction of the incremental signals and the direction of the digital commutation signals are different for encoders which have digital commutation signals (i.e. AB Servo)
2. The direction of the SINCOS signals are incorrect for a SINCOS encoder with comms.

Parameter | 03.057 P1 Normalisation Turns
--- | ---
Short description | Defines the number of turns bits included in the normalisation parameters
Mode | RFC‑S
Minimum | 0 | Maximum | 16
Default | 16 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

The combination of P1 Revolution/Pole Pitch Counter (03.028), P1 Position (03.029) and P1 Fine Position (03.030) give the position feedback as a 48 bit value. This position cannot be read atomically without locking the position feedback (P1 Feedback Lock (03.050) = 1) and it cannot be used directly by the Advanced Motion Controller (see Menu 31). It is useful to be able to create 32 bit position values that can be held by a single parameter as this value can be accessed atomically and can be used directly by the Advanced Motion Controller. P1 Normalisation Turns (03.057) defines the number of turns bits included in the following parameters.

P1 Normalised Position (03.058)
P1 Normalised Marker Position (03.059)
F1 Normalised Freeze Position (03.103) if P1 is the source position for freeze function F1
F2 Normalised Freeze Position (03.108) if P1 is the source position for freeze function F2

Parameter | 03.058 P1 Normalised Position
--- | ---
Short description | Displays the position taken from the position feedback device including the effect of the marker function
Mode | RFC‑S
Minimum | -2147483648 | Maximum | 2147483647
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P1 Normalised Position (03.058) is the position taken from the position feedback device including the effect of the marker function. See P1 Normalisation Turns (03.057) for details of the format.

Parameter | 03.059 P1 Normalised Marker Position
--- | ---
Short description | Displays the normalised position at the last marker event
Mode | RFC‑S
Minimum | -2147483648 | Maximum | 2147483647
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P1 Normalised Marker Position (03.059) is the value P1 Normalised Position (03.058) at the last marker event provided bit 2 of P1 Marker Mode (03.031) is set to 1. See P1 Marker Mode (03.031) for more details.

Parameter | 03.060 P1 Calculation Time
--- | ---
Short description | Defines the time from the first edge of the clock signal from the position feedback interface until the encoder has calculated the position and is ready to return this information
Mode | RFC‑S
Minimum | 0 | Maximum | 20
Default | 5 | Units | µs
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Device Type (03.038): EnDat, BiSS
P1 Calculation Time (03.060) is the time from the first edge of the clock signal from the position feedback interface until the encoder has calculated the position and is ready to return this information. This is used to calculate the overall time for a message interchange with the encoder. See P1 Low Speed Update Rate Active (03.063) for more details.

P1 Device Type (03.038): EnDat 3
P1 Calculation Time (03.060) is the time between the position being latched in the encoder and the position response data all arriving at the drive. The position is latched on the rising edge of the last request pre-amble bit. The time between the latch and the position arriving back at the drive is always calculated when discovering the encoder on initialisation. This is used to calculate the overall time for a message interchange with the encoder so that the request can be triggered in advance of the position datum to provide the position in time. As this time includes the encoders internal processing delay and the line delay, P1 Recovery Time (03.061) and P1 Line Delay Time (03.062) are not used for this device so will always be set to the minimum parameter values. The time is rounded to the nearest microsecond, so the actual value may be up to 500ns more/less than shown. This value is provided for indication only as it will always be low-enough to support fast update rates if required. See P1 Low Speed Update Rate Active (03.063) for more details on comms encoders timing.

P1 Device Type (03.038): Any other type of device
P1 Calculation Time (03.060) has no effect.

Parameter | 03.061 P1 Recovery Time
--- | ---
Short description | Defines the time that must be allowed after each message interchange before a new message begins
Mode | RFC‑S
Minimum | 4 | Maximum | 100
Default | 30 | Units | µs
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Device Type (03.038): EnDat, SSI, BiSS
P1 Recovery Time (03.061) is the time that must be allowed after each message interchange before a new message begins.

P1 Device Type (03.038): Any other type of device
P1 Recovery Time (03.061) has no effect.

Parameter | 03.062 P1 Line Delay Time
--- | ---
Short description | Displays the transmission delay between the position feedback interface and the encoder and back again
Mode | RFC‑S
Minimum | 0 | Maximum | 5000
Default |  | Units | ns
Type | 16 Bit User Save | Update Rate | Background read, position feedback initialisation write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P1 Device Type (03.038): EnDat, SC EnDat, BiSS, SC BiSS
During position feedback initialisation the transmission delay between the position feedback interface and the encoder and back again is measured and stored in P1 Line Delay Time (03.062). This value is then used to compensate for this delay so that the clock/data skew does not prevent the data from the encoder from being read. This means that longer line lengths can be used with these feedback devices provided the correct cable and connection arrangements are used. Line delay compensation is used with both EnDat 2.1 and EnDat 2.2 encoders.

P1 Device Type (03.038): Any other type of device
P1 Line Delay Time (03.062) is always zero.

Parameter | 03.063 P1 Low Speed Update Rate Active
--- | ---
Short description | Indicates when the low speed update rate is active
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default |  | Units |
Type | 1 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P1 Device Type (03.038): EnDat, SSI, BISS, EnDat 3
There is a delay when the position information is obtained via a communications interface from an encoder. It is assumed that the position information is taken from all types of encoder at a fixed datum point during each sample period. The drive initiates the comms transfer at a suitable point in advance of the datum to ensure that the position information is available when required. A correction is then applied to the position information based on the change of position over the previous sample and the advance time so that the position appears to have been sampled at the datum. If the communications exchange, including allowing the encoder a recovery time (P1 Recovery Time (03.061)), is completed in 60μs and the time required to obtain the full position is completed in 40μs then the position is sampled at each current controller task and P1 Low Speed Update Rate Active (03.063) = 0. Otherwise if the communication exchange is completed in 230μs the position is sampled every 250μs and P1 Low Speed Update Rate Active (03.063) = 1. If the complete exchange takes any longer an Encoder 8 trip is initiated. The following table shows the calculations used by the drive to determine the necessary time to obtain the required data.

It should be noted that the faster sample rate is only used if the position feedback is being used for motor control (i.e. the drive in operating in RFC-A or RFC-S mode and Motor Control Feedback Select (03.026) = P1 Drive (0)). If this is not the case the communication exchange is completed in 250us and P1 Low Speed Update Rate Active (03.063) = 1.

Protocol | Time for full position | Time for complete data exchange
Endat 2.1 encoder | tST + tD + 10T + 2T + NtT + 5T where tcal ≤ tST + tD/2+ 10T tST + tD + tcal + 2T + NtT + 5T where tcal > tST + tD/2 + 10T | Time for full position + tm
EnDat 2.2 encoder | tST + tD + 10T + 3T + NtT + 5T + tAdd where tcal ≤ tST + tD/2+ 10T tST + tD + tcal + 3T + NtT + 5T + tAdd where tcal > tST + tD/2 + 10T | Time for full position + tm
BiSS | tD + tcal + 2T + NtT + 2T + (CRCBits x T) | Time for full position + tm
SSI | tD + T + NtT (tD cannot be measured, and so a value of 1.25μs is used) | Time for full position + tm
EnDat 3* | tLatch + tcal | Time for full position + tLPD

where

Value | Description | Source
tST | EnDat start time | For 100K baud = 5us, 200K baud = 2.5us, for all other baud rates = 2μs
tD | Transmission delay from the drive to the encoder and back | P1 Line Delay Time (03.062)
T | 1 / baud rate | P1 Comms Baud Rate (03.037)
tcal | Position calculation time | P1 Calculation Time (03.060)
Nt | Total number of position information bits | P1 Comms Bits (03.035)
tm | Encoder recovery time | P1 Recovery Time (03.061)
tAdd | Time for additional information | tAdd1 = 31T + tST + 30T
CRCBits | The number of bits in the CRC applied to the position | P1 Additional Configuration (03.074)
tLatch | Time between start of request and position latched in the encoder | 1100ns (100ns start delay, 25 pre-amble half-bits = 1000ns)
tLPD | Time for low-priority data (i.e. non-control position data) to be received after datum | 7.84us (low-priority header = 64 half-bits, low-priority frame = 128 half-bits, post-amble = 4 half-bits => 196 half-bits => 196 * 40ns)

*EnDat 3 timings are provided for reference but these exchanges are always short enough to support fast updates if the drive requests this.

P1 Device Type (03.038): Any other type of device
P1 Low Speed Update Rate Active (03.063) is always zero.

Parameter | 03.064 P1 Encoder Protocol Detected
--- | ---
Short description | Defines which protocol is used with the device P1
Mode | RFC‑S
Minimum | 0 | Maximum | 5
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, TE, ND, NC, PT

Value | Text
0 | None
1 | Hiperface
2 | EnDat2.1
3 | EnDat2.2
4 | BiSS
5 | Endat3

P1 Encoder Protocol Detected (03.064) shows the encoder comms protocol detected during position feedback initialisation. If communications is not successful during initialisation then P1 Encoder Protocol Detected (03.064) is set to None [0], otherwise it will be set as follows depending upon the discovered protocol:

P1 Device Type (03.038) | P1 Encoder Protocol Detected (03.064)
SC Hiperface | Hiperface [1]
EnDat or EnDat Alt | EnDat2.1 [2] or EnDat2.2 [3]
Endat 3 | EnDat3 [5]
SC BiSS, BiSS or BiSS Alt | BiSS [4]
All other devices | None [0]

Parameter | 03.065 P1 Resolver Poles
--- | ---
Short description | Defines the number of poles for the resolver connected to P1
Mode | RFC‑S
Minimum | 1 | Maximum | 15
Default | 1 | Units | PolePairs
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Device Type (03.038): Resolver
P1 Resolver Poles (03.065) should be set to the number pole pairs for the resolver connected to the P1 position feedback interface. If the resolver is being used for motor control then a 2 pole resolver can be used with any motor, but if the number of resolver poles is greater than 2, it can only be used when motor poles / resolver poles is an integer (i.e. a 4 pole resolver can be used with an 8 pole motor). Note that this value is only used if P1 Linear Feedback Select (03.051) = 0. If not then the position feedback must be set up using P1 Linear Line Pitch (03.053) and P1 Pole Pair Pitch (03.055).

P1 Device Type (03.038): SC Hiperface, SC EnDat, SC SSI, SC BiSS
The communications from a SINCOS encoder provides the position that is used each time the position feedback interface is initialised so that the encoder can give an absolute position even though the sine wave signals only give an incremental position. Normally the comms position gives a change of position equivalent to one turn for each mechanical rotation. Some systems, particularly where the position feedback is simulated from a different feedback device, give a change of comms position that is equivalent to more than one turn for each mechanical rotation. This parameter defines a right shift that is applied to the comms position to compensate for this effect. In the example shown below the comms position changes by one turn for half a mechanical revolution. In this case this parameter should be set to 4 poles (2). This divides the position by two so that the resolution is now the same as the position from the sine wave signals. However the absolute position is no longer unique, and so this can only be used for motor control feedback with a motor that has a multiple of 4 poles, i.e. 4 poles, 8 poles, etc. (Note that the turns information is always set to zero if a shift is applied.)

The shift applied is shown in the table below.

P1 Resolver Poles (03.065) | Shift right by number of bits given
2 poles (1) | 0
4 poles (2) | 1
6 poles (3) | 2
8 poles (4) and higher | 3

P1 Device Type (03.038): Any other type of device
P1 Resolver Poles (03.065) has no effect.

Parameter | 03.066 P1 Resolver Excitation
--- | ---
Short description | Defines the excitation of the resolver when connected to P1
Mode | RFC‑S
Minimum | 0 | Maximum | 7
Default | 5 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | 6kHz 3V
1 | 8kHz 3V
2 | 6kHz 2V
3 | 8kHz 2V
4 | 6kHz 3V Fast
5 | 8kHz 3V Fast
6 | 6kHz 2V Fast
7 | 8kHz 2V Fast

P1 Device Type (03.038): Resolver
P1 Resolver Excitation (03.066) defines the excitation voltage and frequency. A level of 3V r.m.s. should be used with 3:1 resolvers and 2V r.m.s. with 2:1 resolvers. These give a nominal level of 1V r.m.s. feedback into the position feedback interface. Other ratios can be used, but if the feedback is increased above the expected levels the feedback seen by the drive will be distorted. The resolution of the position feedback will be reduced proportionally if the feedback is less than 1V r.m.s. With a 2 pole resolver the nominal resolution is equivalent to 16384 line encoder. If the number of resolver poles are increased then the resolution increases, for example a 4 pole resolver gives a resolution equivalent to a 32768 line encoder, etc. The position feedback system allows for a delay from the excitation to the feedback from the resolver of up to 45o and will compensate for this lag during the position feedback initialisation process. (It should be noted that the excitation voltage given is the nominal level, but this can slightly higher than the nominal level.)

The resolver interface offers two sampling rates: standard and fast.

- With standard sampling (P1 Resolver Excitation (03.066) < 4) any switching frequency can be used with any resolver excitation frequency and the switching frequency can be changed when the position feedback is being used without any transient effects. There is a 250us sampling delay with this system and if the resolver feedback is used for motor control the system can become unstable at high speeds. It is recommended that the motor speed is limited to 9000rpm / Motor Pole Pairs.
- With fast sampling (P1 Resolver Excitation (03.066) ≥ 4) the sample delay is significantly reduced and resolver feedback can be used up to the maximum limit of 30000rpm / Resolver Pole Pairs, but the feedback is slightly noisier and the acoustic noise produced by the motor is increased. It is possible to switch between standard and fast sampling while the drive is enabled and controlling a motor, so for example standard sampling can be used at low speeds, and then fast sampling can be used at higher speeds.

Normally when P1 Resolver Excitation (03.066) is changed an Encoder 7 is initiated because the position feedback set-up has been changed and the position feedback interface needs to be re-initialised. However, if the new value of P1 Resolver Excitation (03.066) is the old value plus or minus 4 (i.e. 0 to 4, or 5 to 1, etc.) then a trip is not initiated and the interface does not need to be initialised.

The following restrictions apply if fast sampling is selected:

1. 2, 4, 8 or 16kHz switching frequencies should be used with 8kHz excitation. 3, 6 or 12kHz switching frequencies should be used with 6kHz excitation. If these conditions are not met the system will automatically operate with standard sampling.
2. If the switching frequency is changed by one step, i.e. from 2 to 3kHz, there will be a transient in the position feedback. To ensure that this does not happen as the drive alters the switching frequency because it has become too hot Auto-switching Frequency Step Size (05.036) should be left at its default value, so that all changes are made in steps of 2.
3. If the resolver feedback is not being used as the feedback for motor control then its sample rate is automatically reduced and the position feedback will automatically operate with standard sampling.

P1 Device Type (03.038): Any other type of device
P1 Resolver Excitation (03.066) has no effect

Parameter | 03.067 P1 User Comms Enable
--- | ---
Short description | Enables the use of the user comms parameters to communicate to the encoder connected to P1
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 8 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, NC, PT

If P1 User Comms Enable (03.067) set to one it is possible to use P1 User Comms Transmit Register (03.068) and P1 User Comms Receive Register (03.069) to communicate with an encoder that has a Hiperface, EnDat 2.1, EnDat2.2, EnDat 3 or BiSS interface. A description of how to use these registers is given below.

P1 Device Type (03.038): SC Hiperface, SC EnDat
Hiperface or EnDat 2.1 communications are used as appropriate if P1 User Comms Enable (03.067) is set to one.

P1 Device Type (03.038): EnDat, EnDat 3
Communication is enabled when P1 User Comms Enable (03.067) is set to one. If the encoder supports EnDat 2.2 or EnDat 3 it is possible to enable user communications at any time even if the drive is enabled. Otherwise if the encoder only supports EnDat 2.1 communication with the encoder is not possible.

P1 Device Type (03.038): BISS, SC BiSS
If P1 User Comms Enable (03.067) is set to one it is possible to enable user communications at any time even if the drive is enabled.

Encoder communications
A communication channel is provided to allow the user to communicate with an encoder connected to one of the communications interfaces. It should be noted that the communications channel is disabled under the following conditions:

1. If auto-configuration is active.
2. During the transfer of electronic nameplate data.
3. If the position feedback device is not initialised.
4. The channel is being used by an option module with safety functions.

To send a message to the encoder the required message must be written to the transmit register. To read the response from the encoder the data is read from the receive register. The data is written one byte at a time and is stored in a 16 byte buffer before being sent to the encoder. The data should only be written to the transmit register when it has been cleared to zero by the drive. Bits 13 to 15 are used to control the interface.

Bit | Function
15 | This bit should be set to one each time data is written to the transmit register. This indicates that data has been written. This bit will be cleared when the LS byte of the data has been transferred into the comms buffer.
14 | This bit should be set when the last byte of the message is written to the transmit register. The data will be read and transferred to the comms buffer and then the message will be sent to the encoder.
13 | This bit should be set when the first byte of the message is written to the transmit register. Setting this bit will reset the pointer to the start of the comms buffer.

Data can be read from the receive register at any time. If there is data in the buffer bit 15 will be set. Once the data has been read the register should be cleared and the drive will transfer the next byte of data to the register.

Bit | Function
15 | Indicates that data from the last transfer can be read from the receive register.
14 | Indicates that the last byte from the receive message is in the register.
13 | There is no data in the receive buffer and the LS byte of the receive register is the comms system status. If there was an error in the received message one of the status error bits will also be set until the comms is used again by this system or by the drive.

Note: whilst the drive is waiting for the encoder to respond, bit 13 will be set but the status will be zero until either data is available or an error occurs. Therefore, when bit 13 is set the status should only be used if it is non-zero or some data has already been received.

The status flags are defined as follows:

Bit | Meaning
0 | The number of bytes put into the transmit buffer is not consistent with the expected message length. (Hiperface only)
1 | The number of bytes written to the transmit buffer, or the expected length of the store data transmit message, or the expected length of a read data message have exceed the length of the buffer. (Hiperface only)
2 | The command code is not supported.
3 | A valid response was not received from the encoder.
4 | An attempt was made to access a forbidden location (BiSS only).
5 | Other error has occurred, see encoders error code in data buffer if the supported device provides this (EnDat 3 only).

The following sequence should be followed when transmitting and receiving data to ensure that the received data is always read correctly.

1. Check that P1 User Comms Receive Register (03.069) is not zero.
2. Check that P1 User Comms Transmit Register (03.068) is zero.
3. Write each word of the transmit message to P1 User Comms Transmit Register (03.068) in turn, waiting each time for the drive to return P1 User Comms Transmit Register (03.068) back to zero before writing the next word.
4. Write zero to P1 User Comms Receive Register (03.069).
5. Read P1 User Comms Receive Register (03.069) and when it is not zero the drive has updated it with a receive word.
6. Read each receive word in turn writing zero to P1 User Comms Receive Register (03.069) after reading the word.

If the above sequence is not followed correctly, it is possible that data from the transmit message will be seen in the first read of the receive message. It is not essential that any or all of the receive message is read before sending a new transmit message, and so steps 4 to 6 can be omitted if required provided step 1 is not ignored.

Hiperface
Up to 15 bytes of data can be written to the buffer. The first byte should be the encoder address. The checksum will be calculated by the drive and added to the end of the message before the message is transmitted to the encoder. The drive checks the checksum of the received message. If successfully received, the receive message can be read via the receive register including the address and the checksum received from the encoder. It should be noted that the encoder must be set up for 9600 baud, 1 start bit, 1 stop bit and even parity (default set-up) for the encoder comms to operate with the drive. Also the data block security should not be enabled in the encoder if the drive encoder nameplate system is to operate correctly. See Hiperface specification for more details of the comms message format.

The following commands are supported:

Code | Command
0x42 | Read position
0x43 | Set position
0x44 | Read analog value
0x46 | Read counter
0x47 | Increment counter
0x49 | Clear counter
0x4a | Read data (maximum of 10 bytes)
0x4b | Store data (maximum of 9 bytes)
0x4c | Data field status
0x4d | Create a data field
0x4e | Available memory
0x50 | Read encoder status
0x52 | Read type
0x53 | Reset encoder
0x56 | Read serial number and program version*

*For all other commands the receive message length including the address and checksum is limited to 16 bytes. Command 0x56 produces a response of between 20 and 40 bytes. For this command the response can be received correctly up to 40 bytes.

SC Endat
Up to 4 bytes can be written to the buffer is the following format.

Byte 0 |  |  |
Command | Address | Data (MSB) | Data (LSB)

The following commands are supported.

Code | Command | Address | Data (MSB) | Data (LSB)
0x07 | Encoder to send position value | Any | Any | Any
0x0E | Selection of memory area | MRS code | Any | Any
0x1C | Encoder to receive parameter | Address | Data (MSB) | Data (LSB)
0x23 | Encoder to send parameter | Address | Any | Any
0x2A | Encoder to receive reset | Any | Any | Any

The message from the encoder contains a CRC which is checked. If there are no errors in the message, then the message is put into the comms buffer. The position is retrieved from the drive buffer most significant byte first (Byte 0) and least significant byte last (Byte 7). An example is shown below where a 48 bit value has been read from the encoder which contains an error bit (Bit 0) and 47 bits of position data (Bits 1 to 47) where Bit 1 is the least significant bit of the position. If there are less position bits the position is right justified with leading zeros.

Byte 0 |  |  |  |  |  |  | Byte 7
0 | 0 | Bits47-40 | Bits 39-32 | Bits 31-24 | Bits 23-16 | Bits 15-8 | Bits 7-0

If any other command is sent the response is shown below. The response is available when the encoder has responded, but for "Encoder to receive parameter" and "Encoder to receive reset" commands there is an additional delay of 12ms and 20ms respectively to allow the encoder to be ready again.

Byte 0 |  | Byte 2
Address | Data (MSB) | Data (LSB)

EnDat
Up to 4 bytes can be written to the buffer in the same format as for EnDat 2.1. The following commands are supported.

Code | Command | Address | Data (MSB) | Data (LSB)
0x09 | Encoder to send position value with additional information and select memory area | MRS code | 0x00 | Block address
0x1B | Encoder to send position value with additional information and receive parameters | Address | Data (MSB) | Data (LSB)
0x24 | Encoder to send position value with additional information and send parameters | Address | Any | Any
0x2D | Encoder to send position value with additional information and receive error reset | Any | Any | Any
0x36 | Encoder to send position values and receive test command | Any | Any | Any

The message from the encoder contains a CRC which is checked. If there are no errors in the message the message is put into the comms buffer.

Byte 0 |  | Byte 2
Additional information 1 Byte 0 (B7) WRN (B6) RM (B5) Busy (B4) I4 (B3) I3 (B2) I2 (B1) I1 (B0) I0 | Additional Information 1 Byte 1 | Additional Information 1 Byte 2

It should be noted that the encoder is set up automatically so that it always returns Additional Information 1 with no data contents. An MRS is sent to the encoder to select which data contents should be included in Additional Information 1. An MRS code can also be used to select Additional Information 1, Additional Information 2 or no Additional Information to be sent from the encoder, but these commands must not be used. Although the contents of Additional Information 1 can be changed the encoder should always be in the state where it transmits only Additional Information 1.

EnDat 3
The drive provides access to both encoder memory via background access and low-priority data via foreground requests using the user comms channel.

Request data format:

If the request message is 6 bytes, it is assumed access to the background channel has been requested, otherwise if the request message is a single byte it is assumed to be a request to get the low-priority data for the user specified FID set up on initialisation:

Request byte | Background comms mode | User foreground comms mode*
0 | Background request word 0 LSB | 0x01 (User channel 1), 0x02 (User channel 2)
1 | Background request word 0 MSB |
2 | Background request word 1 LSB |
3 | Background request word 1 MSB |
4 | Background request word 2 LSB |
5 | Background request word 2 MSB (BG op-code) |

*These user comms codes action a read of the required custom low-priority foreground data set up on initialisation (set in P1 Additional Configuration Information (03.072)). Once the requested low-priority (LPF) data has been read and cached by the drive, the response will be returned via the receive parameter.
Response data format:

Response byte | Background comms mode | User foreground comms mode
0 | Background response byte 0 | Low-priority frame byte 0 (status)
1 | Background response byte 1 | Low-priority frame byte 1 (data 0)
2 | Background response byte 2 | Low-priority frame byte 2 (data 1)
3 | Background response byte 3 | Low-priority frame byte 3 (data 2)
4 | Background response byte 4 | Low-priority frame byte 4 (data 3)
5 | Background response byte 5 | Low-priority frame byte 5 (data 4)
6 |  | Low-priority frame byte 6 (data 5)
7 |  | Low-priority frame byte 7 (crc)

The following table shows data in the request and response for the supported background op-codes:

Read request:

Byte | Request | Response
0 | Num of words to read (1-3) | Word 0 read (LSB)
1 | Always zero (0x00) | Word 0 read (MSB)
2 | 24-bit memory address to read from (bits 0:7) | Word 1 read (LSB)*
3 | 24-bit memory address to read from (bits 8:15) | Word 1 read (MSB)*
4 | 24-bit memory address to read from (bits 16:23) | Word 2 read (LSB)*
5 | Read op-code (0x02) | Word 2 read (MSB)*

*these words will be zero if only 1 (or 2 for response word 2) words have been requested for reading.

Write request:

Byte | Request | Response
0 | Word to write (LSB) | Word written (LSB)
1 | Word to write (MSB) | Word written (MSB)
2 | 24-bit memory address to write to (bits 0:7) | Always zero (0x00)
3 | 24-bit memory address to write to (bits 8:15) | Always zero (0x00)
4 | 24-bit memory address to write to (bits 16:23) | Always zero (0x00)
5 | Write op-code (0x03) | Always zero (0x00)

All other request op-codes will be rejected by the drive and the status will indicate the failed access. The memory area OEM1 (0x050000) is where the electronic nameplate is stored. See the EnDat 3 interface specification for other memory areas and offsets. The memory area LPFLIVE (0x090000) is set up by the drive during initialisation and once initialised is required for correct operation so writing to this area will be rejected by the drive. It will respond that the command is not supported.

BiSS, SC BiSS
It is possible to read or write to 8 bit registers in a BiSS device. The addressing range is 0 to 127. Two bytes should be written to the buffer for both read or write operations. Byte 0 contains the command in bit 7 (0 = read, 1= write) and the register address in bits 6 to 0. For reading Byte 1 can contain any value, for writing it should contain the data to be written. It should be noted that BiSS encoders have a bank system that allows more than 128 locations to be addressed. The first 64 addresses can be accessed in multiple banks by setting the bank number at address 0x40. See BiSS specifications for more details.

Byte 0 | Byte 1
Command + Address | Data

The response is always two bytes as shown below. Byte 0 is the same as Byte 0 in the request sent to the drive. For reading Byte 1 is the value read from the register, and for writing it should be the byte that was written.

Byte 0 | Byte 1
Command + Address | Data

Parameter | 03.068 P1 User Comms Transmit Register
--- | ---
Short description | Defines the value present in the user comms transmit register
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default | 0 | Units |
Type | 16 Bit Volatile | Update Rate | Background read/write
Display Format | Standard | Decimal Places | 0
Coding | RW, NC, PT, BU

See P1 User Comms Enable (03.067).

Parameter | 03.069 P1 User Comms Receive Register
--- | ---
Short description | Defines the value present in the user comms receive register
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default | 0 | Units |
Type | 16 Bit Volatile | Update Rate | Background read/write
Display Format | Standard | Decimal Places | 0
Coding | RW, NC, PT, BU

See P1 User Comms Enable (03.067).

Parameter | 03.070 P1 Position Feedback Signals
--- | ---
Short description | Shows the state of the signals from the position feedback device
Mode | RFC‑S
Minimum | 0 (Display: 000000) | Maximum | 63 (Display: 111111)
Default |  | Units |
Type | 16 Bit Volatile | Update Rate | Background write
Display Format | Binary | Decimal Places | 0
Coding | RO, ND, NC, PT

P1 Position Feedback Signals (03.070) shows the state of the signals from the position feedback device as given in the table below where the signals are relevant for the type of device. P1 Position Feedback Signals (03.070) is only intended as a debugging aid.

P1 Position Feedback Signals (03.070) bits | Signals
0 | A or F or Cos
1 | B or D or R or Sin
2 | Z
3 | U
4 | V
5 | W

For Cos and Sin signals the relevant bits of P1 Position Feedback Signals (03.070) will be set when the signals are positive and cleared when the signals are negative.

Parameter | 03.071 P1 Error Detected
--- | ---
Short description | Indicates if an error has been detected with the position feedback device connected to the P1 position interface
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default |  | Units |
Type | 1 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P1 Error Detected (03.071) is set if an error has been detected with the position feedback device connected to the P1 position interface. This parameter is useful if encoder trips have been disabled by setting bit 3 of P1 Error Detection Level (03.040). It should be noted that this bit is not set if specific trips are disabled with bits 0 to 2 of P1 Error Detection Level (03.040).

Parameter | 03.072 P1 Additional Configuration Information
--- | ---
Short description | Additional information obtained from the device connected to the P1 interface during auto-configuration.
Mode | RFC‑S
Minimum | 0 | Maximum | 2147483647
Default | 0 | Units |
Type | 32 Bit Volatile | Update Rate | Background Write
Display Format | Standard | Decimal Places | 0
Coding | RO, PT

P1 Additional Configuration Information (03.072) displays additional information obtained from the position feedback device during auto-configuration that is not shown in any other parameters.

P1 Device Type (03.038): BiSS, SC BiSS, BiSS Alt

This parameter is split into 2 fields:

Decimal Digits | 5-3 | 2-0
| User area start page | User area end page

User area start page is the first page of memory within the encoder for storing user data. If an electronic nameplate is stored within the encoder it will normally start at the beginning of this page. If there is no memory assigned for user data this will have a value of 0.

User area end page is the last page of memory within the encoder for storing user data. If user area start page is 0 then this value will also be 0.

P1 Device Type (03.038): Any other type
This parameter is zero.

Parameter | 03.073 P1 Absolute Turns Recovery Enable
--- | ---
Short description | Set to 1 to allow turns information beyond the number of turns bits provided by the position feedback device connected to P1 to be stored on power-down and recovered at next power-up
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Absolute Turns Recovery Enable (03.073) can be used to remove the masking applied to P1 Revolution/Pole Pitch Counter (03.028) for any type of position feedback device. If P1 Device Type (03.038) is set to EnDat, SC.EnDat, EnDat 3, SC.Hiperface, SSI, SC.SSI, and BiSS then this parameter has an additional feature which allows turns bits beyond the number of turns bits provided by the position feedback device to be stored on power-down and then recovered on the next power-up. P1 Revolution/Pole Pitch Counter (03.028) is saved as a power-down save parameter. If P1 Absolute Turns Recovery Enable (03.073) = 0 the value saved at power-down is ignored on the next power-up and P1 Revolution/Pole Pitch Counter (03.028) is set up based on the information provided by the position feedback device. For example a device with 12 turns bits can define the position with up to 4096 turns. If P1 Absolute Turns Recovery Enable (03.073) = 1 the turns beyond those provide by the position feedback device are simulated from the saved value. This means that 65536 turns can be generated from a position feedback device with any number of turns bits. The following should be noted:

1. If the position feedback device moves by more than +/-1/4 of the range of the most significant turns bit while powered down the turns at power-up will not be correct. For example a device with 12 turns bits must not move by more than the range defined by 10 turns bits, or a device with no turns bits must not move by more than 1/4 of a turn.
2. This feature is not applicable to linear position feedback devices.
3. If an SSI based device is being used then P1 SSI Incremental Mode (03.047) must be set to one.
4. The recovered turns bits are stored in P1 Revolution/Pole Pitch Counter (03.028). To reset the additional bits P1 Absolute Turns Recovery Enable (03.073) should be set to zero to remove the recovered turns bits. A parameter save should then be initiated using a value of 1 or 1001 in parameter mm.000 to save the contents of P1 Revolution/Pole Pitch Counter (03.028). Absolute turns recovery can then be selected again by setting P1 Absolute Turns Recovery Enable (03.073) to one.
5. Absolute turns recovery is not possible when Low Under Voltage Threshold Select (06.067) = 1 or Backup Supply Mode Enable (06.068) = 1 or User Supply Select (06.072) = 1. If absolute turns recovery is required when one of these modes is enabled then a user save (Parameter mm.000 (mm.000) = 1 or 1001) should be performed before the drive is powered down.

Parameter | 03.074 P1 Additional Configuration
--- | ---
Short description | Provides additional configuration information for the position feedback device not included in the other set-up parameters.
Mode | RFC‑S
Minimum | 0 | Maximum | 511116116
Default | 0 | Units |
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P1 Additional Configuration (03.074) provides configuration information, not covered by the other set-up parameters, for the position feedback device connected to the P1 position feedback interface and is specific to the type of device being used.

P1 Device Type (03.038): BiSS, SC BiSS

This parameter is split into 3 fields as shown below.

Decimal Digits | 9-6 | 5-3 | 2-0
| CRC polynomial | Rotary Turns Padding | Rotary Position Padding

CRC polynomial

The CRC polynomial is a bit representation of the terms of a polynomial used to generate the CRC applied to the position data as shown above. The normal CRC polynomial is X6+X1+1 which is defined by the binary number 0 0100 0011 (0x43 hexadecial, 67 decimal). X6+X1+1 produces a 6 bit polynomial (as shown above), but by selecting different polymonials is it possible to change the number of bits. P1 Additional Configuration (03.074) is set to 67000000 during auto-configuration giving no zero padding and the standard CRC used with most BiSS encoders. However, if a different polynominal is requried then auto-configuration should be disabled and the required value should be set in this parameter. It should be noted that a different polynomial is used with control communications based on the CDM/CDS bits to read/write data from/to the encoder. This other CRC is fixed for all BiSS encoders and is not affect by this parameter.

Rotary Turns Padding
The turns, and position within a turn, provided by a rotary encoder may not completely fill the number of bits provided. The unfilled bits will normally be padded with zeros. The total number of bits provided for the turns including zero padding is given by P1 Rotary Turns Bits (03.033). The zero padding is given by decimal digits 5 to 3 of P1 Additional Configuration (03.074). Digits 4 and 3 give the number of bits and digit 5 specifies whether the padding is on the left (0) or on the right (1). For example a value of 104 would specify 4 padding bits on the right of the turns data. The default value of 000 specifies no padding. If the padding value is outside the range +/-16 then an Encoder 14 is initiated. If right padding is specified the turns data will be shifted right by the number of padding bits as shown below. If left padding is specified it simply means that there are zeros to the left of the turns information, and so no adjustment is required. Therefore specifying left padding is optional. It is not possible to specify padding for linear encoders.

Data from encoder with 4 right padding bits

1 | 0 | 1 | 1 | 0 | 0 | 0 | 0

Data after adjustment for padding bits

0 | 0 | 0 | 0 | 1 | 0 | 1 | 1

Rotary Position Padding
The total number of bits provided for position within a turn is given by P1 Comms Bits (03.035) - P1 Rotary Turns Bits (03.033). The zero padding is given by decimal digits 2 to 0 of P1 Additional Configuration (03.074) in the same manner as is used for the turns padding. If left padding is specified the turns data will be shifted left by the number of padding bits as shown below. If right padding is specified it simply means that there are zeros to the right of the position information, and so no adjustment is required. Therefore specifying right padding is optional.

Data from encoder with 4 left padding bits

0 | 0 | 0 | 0 | 1 | 0 | 1 | 1

Data after adjustment for padding bits

1 | 0 | 1 | 1 | 0 | 0 | 0 | 0

P1 Device Type (03.038): EnDat 3
The user comms channel allows access to user specified low-priority data frames. This might be used to access sensor or OEM specific data that is not accessible via the usual background memory access. The data required is specifed by the frame identifier (FID), which is a 7-bit value. The FIDs are specified in each byte of P1 Additional Configuration (03.074) and are used to set up the low-priority send lists during initialisation. This firmware release supports up to two custom FIDs.

Parameter bits | 31-24 | 23-16 | 14-8 | 6-0
| Not used | Not used | USER FID 2 | USER FID 1

Example: FID 1 = SENSOR_TEMP_INT (0x21), FID 2 = SENSOR_TEMP_M1 (0x22). Additional configuration value = 0x00002221 = 8737.

The example FIDs used above may not be supported by all devices so refer to encoder manufacturer documentation for the supported FIDs. The default FID values (0x00) set up NOP frames, which contain empty data bytes and are always supported. See P1 User Comms Enable (03.067) for more information on accessing the custom low-priority data over the user comms channel. CT Analyser 3 can be used to read the low-priority data for the set up FIDs.

P1 Device Type (03.038): Any other device type
This parameter has no effect.

Parameter | 03.075 Initialise Position Feedback
--- | ---
Short description | Set to 1 to re-initialise any position feedback device connected
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

If Initialise Position Feedback (03.075) is set to one any position feedback devices connected to the drive position feedback interfaces or any position feedback category option modules will be re-initialised.

Parameter | 03.076 Position Feedback Initialized
--- | ---
Short description | Indicates the initialisation state of position feedback devices connected
Mode | RFC‑S
Minimum | 0 (Display: 0000000000) | Maximum | 1023 (Display: 1111111111)
Default |  | Units |
Type | 16 Bit Volatile | Update Rate | Background write
Display Format | Binary | Decimal Places | 0
Coding | RO, ND, NC, PT

Position Feedback Initialized (03.076) contains flags that represent the initialisation state of position feedback devices connected to the drive position feedback interfaces or position feedback interfaces on position feedback category option modules. One indicates that the interface is initialised and zero indicates that the interface is not initialised. The flags are assigned as shown below.

Bit | Position feedback interface
0 | P1 Drive
1 | P2 Drive
2 | P1 Option slot 1
3 | P2 Option slot 1
4 | P1 Option slot 2
5 | P2 Option slot 2
6 | P1 Option slot 3
7 | P2 Option slot 3
8 | P1 Option slot 4
9 | P2 Option slot 4

If no option module, or an option module other than a position feedback category module, is fitted in an option slot then the relevant flag is always set to one. If an attempt is made to enable the drive when any of the flags are zero the drive initiates an Encoder 7 trip. If a drive reset is initiated, the bits in Position Feedback Initialized (03.076) are checked, and if any position feedback devices are not initialised an attempt is made to initialise them.

The table below shows the initialisation process for different position feedback devices that can be connected to the drive.

Encoder types | Initialisation process
AB, FD, FR | None. Initialisation is immediate and is always successful. The position feedback is set to zero on initialisation.
Resolver | None. Initialisation is immediate and is always successful. The revolution counter is set to zero on initialisation.
AB Servo FD Servo FR Servo SC Servo | The absolute position used to control a motor can only be defined accurately after two different changes of state of the UVW commutation signals. Initialisation resets the system that ensures that the UVW signals alone will be used to define the motor position until the encoder has moved through two valid commutation signal state changes. Initialisation is immediate and is always successful. The position feedback is set to zero on initialisation.
SC | The SINCOS interpolation system must be initialised. Initialisation is immediate and is always successful. The position feedback is set to zero on initialisation.
SC Hiperface SC EnDat SC SSI | Auto-configuration if required except SC SSI. The absolute position must be obtained via comms. This may cause a large change in position feedback. The SINCOS interpolation system must be initialised. This may have a small effect on the position feedback.
EnDat BiSS SSI EnDat 3 | Auto-configuration if required (except SSI which does not support this). The absolute position must be obtained via comms. This may cause a large change in position feedback.
SC SC | The absolute position used to control a motor is obtained from the sine and cosine signals provided for one revolution until the marker pulse occurs. The position obtained from the marker pulse is assumed to be a position of zero. Once a marker has occurred the incremental position is used and the single turn sine wave signals are ignored. When the position feedback device is initialised the single turn sine wave signals are used again until another marker event occurs. No part of the initialisation process affects the position feedback seen in parameters, except that the SINCOS interpolation system must be initialised which may have a small effect on the position feedback. Initialisation is immediate and is always successful.

Parameter | 03.078 Sensorless Mode Active
--- | ---
Short description | Indicates that sensorless mode is active
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default |  | Units |
Type | 1 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

If Sensorless Mode Active (03.078) = 0 it indicates that the position feedback selected with Motor Control Feedback Select (03.026) is being used for motor control. If Sensorless Sensorless Mode Active (03.078) = 1 it indicates that the sensorless algorithm is being used instead. See RFC Feedback Mode (03.024) for more information.

Parameter | 03.079 Sensorless Mode Filter
--- | ---
Short description | Defines the filter for the estimated motor speed when sensorless mode is active
Mode | RFC‑S
Minimum | 0 | Maximum | 4
Default | 4 | Units | ms
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | 4
1 | 8
2 | 16
3 | 32
4 | 64

When sensorless mode is active the estimated motor speed can include some unwanted noise. Some motors have concentrated windings which results is flux distortion when the motor is loaded, which in turn causes ripple in the motor currents and additional unwanted components in the calculated speed feedback. This usually has a more significant effect if the motor is running at high speed when the voltage controller may be active to limit the motor voltage. A filter is applied to the speed feedback with a time constant defined by Sensorless Mode Filter (03.079). The default value for this parameter gives the maximum amount of filtering, so that motors which introduce unwanted feedback noise will operate correctly. If the motor does not introduce this type of noise it is possible to reduce the filter time constant to give better dynamic performance when speed control is required.

Parameter | 03.080 Sensorless Position
--- | ---
Short description | Displays the motor position when sensorless mode is active
Mode | RFC‑S
Minimum | -2147483648 | Maximum | 2147483647
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

When the drive is operating without position feedback Sensorless Position (03.080) gives the motor position where the least significant 16 bits represent a movement equivalent to one pole of the motor. The most significant 16 bits represent turns where one turn is the movement associate with one pole. For example in a rotary application with a 4 pole motor, the movement associated with one pole is a mechanical movement of 180°. In RFC-A mode Sensorless Position (03.080) is aligned with the motor flux and voltages, but this has no fixed relationship to the mechanical position of the rotor.

Parameter | 03.085 Encoder Simulation Source
--- | ---
Short description | Defines the source parameter used for the encoder simulation
Mode | RFC‑S
Minimum | 0.000 | Maximum | 59.999
Default | 0.000 | Units |
Type | 16 Bit User Save | Update Rate | Reset read
Display Format | Standard | Decimal Places | 3
Coding | RW, PT, BU

Encoder Simulation Source (03.085) is used to select a parameter as the input to the encoder simulation system. If Encoder Simulation Source (03.085) is zero then no source is selected and the encoder simulation system is disabled. The encoder simulation output connections are shared with the P1 and P2 position feedback interfaces, and so encoder simulation may be disabled because the connections are not available. See Encoder Simulation Status (03.086) for details.

Any parameter can be selected as the source, but it is assumed that the input is a 16 bit value with a range from 0 to 65535 or from -32768 to 32767. The source parameter is treated differently depending on the value of Encoder Simulation Mode (03.088) as given in the table below.

Encoder Simulation Mode (03.088) |
Hardware (0) | Encoder Simulation Source (03.085) must be set to 3.029 for the output to be enabled and the position from the P1 position feedback interface is used and P1 Position (03.029) is the source.
Lines Per Rev (1) or Ratio (2) | If Encoder Simulation Source (03.085) = 3.029 (i.e. P1 Position (03.029) is the source) then P1 Position (03.029) and P1 Fine Position (03.030) are combined as a 16 bit value with 16 bit fractional part as the input to the encoder simulation system, which gives additional output resolution if encoder simulation ratio is greater than unity. Even though parameter 03.029 is only updated every 4ms, when this is selected as the source the encoder simulation output is updated every 250us, and so it is not necessary to change Encoder Simulation Sample Period (03.087) from its default of 0 to prevent bursts of pulses. The encoder simulation system is intended to be used with a 16 bit source parameter. If the source of the encoder simulation system is not a 16 bit parameter then the drive uses the source parameter as follows. 1 bit parameter: Zero extended 8 bit parameter: Sign extended if BU attribute is zero (signed), otherwise zero extended (unsigned) 32 bit parameter: Only the least significant word is used.
SSI (3) | For SSI output mode the number of bits included in the output can be selected (see Encoder Simulation Mode (03.088) for details).

Although Encoder Simulation Source (03.085) is not a standard source parameter in common with other sources the actual source is only changed on drive reset.

Parameter | 03.086 Encoder Simulation Status
--- | ---
Short description | Displays the status of the encoder simulation
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, TE, ND, NC, PT

Value | Text
0 | None
1 | Full
2 | No Marker Pulse

The availability of the encoder simulation output on the 15 way connector on the drive is dependent on the type of feedback device selected with P1 Device Type (03.038). Priority is as follows from highest to lowest priority:

1. P1 position feedback interface
2. Encoder simulation output
3. P2 position feedback interface

Encoder Simulation Status (03.086) shows the status of the encoder simulation output.

0: None
The encoder simulation output is not enabled or is not available.

1: Full
Full encoder simulation with marker output is available.

2: No Marker
Encoder simulation without marker output is available.

Parameter | 03.087 Encoder Simulation Sample Period
--- | ---
Short description | Defines the sample period of the encoder simulation
Mode | RFC‑S
Minimum | 0 | Maximum | 3
Default | 0 | Units | ms
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | 0.25
1 | 1
2 | 4
3 | 16

The update rate of the encoder simulation system is nominally 250μs, i.e. default value of Encoder Simulation Sample Period (03.087), but if the update rate of the source parameter is different, the encoder simulation output will consist of bursts of pulses at the update rate of the parameter. To prevent this and to give a smooth output, the update rate can be adjusted with Encoder Simulation Sample Period (03.087). Encoder Simulation Sample Period (03.087) has no effect if hardware mode is selected, i.e. Encoder Simulation Mode (03.088) = 0.

Parameter | 03.088 Encoder Simulation Mode
--- | ---
Short description | Defines the mode of the encoder simulation
Mode | RFC‑S
Minimum | 0 | Maximum | 3
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Hardware
1 | Lines Per Rev
2 | Ratio
3 | SSI

Encoder Simulation Mode (03.088) defines the encoder simulation output as incremental signals (AB or FD) derived directly via hardware, incremental signals (AB, FD or FR) generated via software or SSI data generated via software.

0: Hardware
The encoder simulation output is derived directly in hardware from the P1 position feedback interface in the drive and the output is derived from the input with negligible delay. The ratio between the input at the P1 interface and the output is either unity or a limited number of binary divider ratios (see Encoder Simulation Hardware Divider (03.089)). Hardware mode only produces an output with AB, FD, FR, SC, SC Hiperface, SC EnDat or SC SSI type devices. It should be noted that with a SINCOS source device the output is based on the zero crossings of the sine wave inputs and does not include interpolation. If Encoder Simulation Hardware Marker Lock (03.090) = 0 the marker output is derived directly from the marker input. If Encoder Simulation Hardware Marker Lock (03.090) = 1 the incremental output signals are adjusted on each marker event so that the A and B are high with an AB type output, or F is high with an FD type output. Marker locking is not recommended if the number of lines per revolution of the encoder simulation source combined with the ratio does not give an encoder simulation output with a multiple of 4 counts per revolution (i.e. between each output marker event) for AB signals, or a multiple of 2 counts for FD signals, because this causes a count error in the system receiving these signals. The input marker pulse width is not adjusted to take account of the divider ratio, but is simply routed from the input to the output. Therefore the output marker pulse becomes shorter with respect to the output incremental signals as the divider ratio is increased.
It should be noted that an output is only produced if the output type is AB or FD and not if the output type is FR.

1: Lines Per Rev
The encoder simulation output is derived via software from the selected source with a resolution defined by Encoder Simulation Output Lines Per Revolution (03.092) with a minimum delay of 250μs which may be extended if Encoder Simulation Sample Period (03.087) is set up for a longer sample period. Note that the number of output lines per revolution apply to a quadrature (AB) type device, and that if FD or FR mode are selected the number of lines per revolution are 2 x Encoder Simulation Output Lines Per Revolution (03.092). The output is derived by applying a ratio and output counter roll-over limit defined by Encoder Simulation Output Lines Per Revolution (03.092) as shown below. The output marker is produced when the output counter is zero.

If P1 Position (03.029) is selected as the source and Encoder Simulation Incremental Mode Select (03.091) = 0 then the input and output counters are synchronised at power-up and when the P1 position feedback interface becomes initialised, so that the output marker is synchronised with zero position for the P1 position feedback interface. For devices that support a marker, the effect of the marker on the position can be selected using P1 Marker Mode (03.031). At power-up and on device initialisation there will be a step change in position from zero to the actual position from the device and the pulses necessary to make this change are produced at the encoder simulation output. If a marker event occurs that causes a step change in position, again the necessary pulses will be produced for this change of position. Where large sudden changes occur the maximum output frequency is limited to 500kHz, and so it may take some time for the output position to reach the input position. This mode of operation gives an initial position change from zero position and then follows all changes of position from that point onwards, and may be used to follow the absolute position of the device connected to the P1 position feedback interface.

If P1 Position (03.029) is selected as the source and Encoder Simulation Incremental Mode Select (03.091) = 1 then the encoder simulation output only follows the changes of source position. At power-up, on device initialisation and a marker event no additional pulses are produced to give the absolute position of the device related to zero position. The encoder simulation output markers is not synchronised to the source marker.

If a source other than P1 Position (03.029) is selected Encoder Simulation Incremental Mode Select (03.091) has no effect and the encoder simulation system always operates in absolute mode.

2: Ratio
The encoder simulation is derived in the same way as described previously for Encoder Simulation Mode (03.088) = 1 (i.e. lines per rev mode), except that different parameters are used to set up the system giving more flexibility as shown below.

With the default settings (Encoder Simulation Numerator (03.093) = 65536, Encoder Simulation Denominator (03.094) = 65536 and Encoder Simulation Output Roll-over Limit (03.095) = 65535) the output produces a state change each time the source parameter changes by one. The numerator and denominator can be changed to provide a different ratio between the source and the output. Output markers are produced each time the output counter is zero and the counters are synchronised in the same way as for lines per rev mode. It is possible to control the roll-over limit of the output counter and hence the rate at which output markers are produced using Encoder Simulation Output Roll-over Limit (03.095). For example, if the ratio is set to 1024/65536 and the roll-over limit is 1023 then one output marker is produced for every 1024 encoder counts (or 256 encoder lines) of output incremental signals. If the roll-over limit is changed to 511, then two output markers are produced for every 1024 encoder counts of output incremental signals.

3: SSI
In this mode the B output becomes the clock input and the A output is the data output. If the source position is the P1 position feedback interface the data from the position feedback interface is transferred to the SSI output register once per sample period defined by Encoder Simulation Sample Period (03.087). An example is given below which shows how the data is aligned.

The SSI output is then clocked out from the register as shown in another example below which includes 15 bits of data.

It should be noted that the data is shifted out by a clock that is produced by the SSI master connected to the encoder simulation interface as the interface is emulating an SSI encoder. However, unlike an SSI encoder the position data is not sampled on the first edge of the clock, but is updated by the drive at the rate defined by Encoder Simulation Sample Period (03.087). If the P1 position interface is being used as the source the power supply alarm bit (PS) is the inverse of the initialised flag in Position Feedback Initialized (03.076) related to this interface. The master can clock out as many bits of data as required, but once the power supply alarm bit has been produced the output will remain low. The SSI interface reset time (tm) of 20μs is required so that the interface can detect the end of the transmission and reset itself so that the output data begins again at the most significant bit. During this period the master should hold the clock line high. The master should not use a clock frequency of less than 50kHz or else spurious reset periods may be detected.

If any other parameter is used as the source the most significant M bits of the source parameter are used, where M = Encoder Simulation SSI Comms Bits (03.097) - 1. If the source parameter has less than M bits then trailing zeros are added. The power supply alarm bit is always zero in this mode.

Parameter | 03.089 Encoder Simulation Hardware Divider
--- | ---
Short description | Defines the divider ratio between the device connected to the P1 interface and the encoder simulation output when hardware simulation mode is used
Mode | RFC‑S
Minimum | 0 | Maximum | 7
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

If hardware mode is selected (i.e. Encoder Simulation Mode (03.088) = 0) then Encoder Simulation Hardware Divider (03.089) defines the divider ratio between the device connected to the P1 position feedback interface and the output as 1/2Encoder Simulation Hardware Divider (03.089). The maximum allowed input frequency is 500kHz, and so the maximum output frequency with the highest ratio of unity is 500kHz.

Parameter | 03.090 Encoder Simulation Hardware Marker Lock
--- | ---
Short description | Defines if the marker output is derived directly from the marker input
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Encoder Simulation Mode (03.088).

Parameter | 03.091 Encoder Simulation Incremental Mode Select
--- | ---
Short description | Set to 1 to select incremental mode for the encoder simulation
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Encoder Simulation Mode (03.088).

Parameter | 03.092 Encoder Simulation Output Lines Per Revolution
--- | ---
Short description | Defines the required lines per revolution when using the encoder simulation mode of Lines Per Rev
Mode | RFC‑S
Minimum | 1 | Maximum | 16384
Default | 4096 | Units |
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Encoder Simulation Mode (03.088).

Parameter | 03.093 Encoder Simulation Numerator
--- | ---
Short description | Defines the numerator when using the encoder simulation mode of Ratio
Mode | RFC‑S
Minimum | 1 | Maximum | 65536
Default | 65536 | Units |
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Encoder Simulation Mode (03.088).

Parameter | 03.094 Encoder Simulation Denominator
--- | ---
Short description | Defines the denominator when using the encoder simulation mode of Ratio
Mode | RFC‑S
Minimum | 1 | Maximum | 65536
Default | 65536 | Units |
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Encoder Simulation Mode (03.088).

Parameter | 03.095 Encoder Simulation Output Roll-over Limit
--- | ---
Short description | Defines the roll-over limit of the output counter and hence the rate at which output markers are produced when using the encoder simulation mode of Ratio
Mode | RFC‑S
Minimum | 1 | Maximum | 65535
Default | 65535 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

See Encoder Simulation Mode (03.088).

Parameter | 03.096 Encoder Simulation SSI Turns Bits
--- | ---
Short description | Defines the number of bits of the outputted SSI data that are used to represent turns information
Mode | RFC‑S
Minimum | 0 | Maximum | 16
Default | 16 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Encoder Simulation Mode (03.088).

Parameter | 03.097 Encoder Simulation SSI Comms Bits
--- | ---
Short description | Defines the total number of bits of SSI data to be outputted
Mode | RFC‑S
Minimum | 2 | Maximum | 48
Default | 33 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See Encoder Simulation Mode (03.088).

Parameter | 03.098 Encoder Simulation Output Mode
--- | ---
Short description | Defines the format of the encoder simulation output
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | AB/Gray
1 | FD/Binary
2 | FR/Binary

Encoder Simulation Output Mode (03.098) is used to select the format of the encoder simulation output as given in the table below.

Encoder Simulation Mode (03.088) | Encoder Simulation Output Mode (03.098) | Format
Hardware (0), Lines Per Rev (1), Ratio (2) | AB/Gray | AB quadrature signals
Hardware (0), Lines Per Rev (1), Ratio (2) | FD/Binary | Frequency and direction signals
Lines Per Rev (1), Ratio (2) | FR/Binary | Forward and reverse signals
SSI (3) | AB/Gray | The position data is in Gray code format. This does not include the “power supply” bit if present.
SSI (3) | FD/Binary, FR/Binary | The position data is in binary format

FR encoder simulation output mode is not available if Encoder Simulation Mode (03.088) is set to Hardware. FR encoder simulation output mode is available if Encoder Simulation Mode (03.088) is set to Lines Per Rev or Ratio.

Parameter | 03.100 F1 Freeze Trigger Source
--- | ---
Short description | Used to select the source that generates trigger events for the F1 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 6
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Digital Input 4
1 | Digital Input 5
2 | P1 Marker
3 | P2 Marker
4 | Common
5 | P1 Zero
6 | P2 Zero

F1 Freeze Trigger Source (03.100) is used to select the source that generates trigger events for the F1 system.

0, 1: Dig I/O 4, Dig I/O 5
Digital I/O 4 or Digital I/O 5 on the drive can be used as trigger sources. If the digital I/O is set up as an input, then trigger events will be produced on the relevant edge of the input signal. If the digital I/O is set up as an output, then trigger events will be produced on the relevant edge of the output signal.

2, 3: Z1, Z2
Z1 selects the P1 position feedback interface marker input as the trigger source and Z2 selects the P2 position feedback interface marker input as the trigger source. No trigger events will be produced unless the selected maker input is available.

4: Common
The output of the common freeze line is selected. If the output of the drive common freeze system is enabled (Bit 3 of Common Freeze Mode (03.112) = 1) then the drive common freeze system provides the freeze event triggers. If the output of the drive common freeze system is disabled the option module freeze line provides the freeze event triggers.

5, 6: P1 Zero, P2 Zero
A freeze event is triggered when the turns for the respective position feedback interface change (i.e. the feedback position passes through zero in either direction). The freeze position stored in F1 Normalised Freeze Position (03.103) or F2 Normalised Freeze Position (03.108) will include the turns associated with the zero position whichever direction the position changes. For example if the turns change from 4 to 5 or 5 to 4 the turns value stored is 5. This mode can be used as a substitute for a physical marker, with a position device that does not have one, to trigger an event to occur at the zero position of the feeback device. For example, it can be used with the AMC to start a CAM at the zero position of the feedback device. It should be noted that if P1 Zero is selected as the trigger source then F1 Freeze Position Source (03.102) has no effect and P1 is always used as the freeze position source. If P2 Zero is selected as the trigger source then F1 Freeze Position Source (03.102) has no effect and P2 is always used as the freeze position source. This is because these freeze trigger sources are only intended to capture the zero position of the device being used to give the zero position trigger event.

Parameter | 03.101 F1 Freeze Mode
--- | ---
Short description | Sets the mode used for the F1 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 3
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Rising 1st
1 | Falling 1st
2 | Rising all
3 | Falling all

0: Rising 1st
Freeze events are produced on the rising edge of the freeze trigger source. If the F1 Freeze Flag (03.104) is 0 then the first suitable edge produced by the trigger source causes the freeze position to be stored and the F1 Freeze Flag (03.104) to be set to 1. No further freeze events are possible until the F1 Freeze Flag (03.104) has been cleared by the user.

1: Falling 1st
As for Rising 1st, but the falling edge is used to trigger freeze events.

2: Rising All
Freeze events are produced on the rising edge of the freeze trigger source. If the F1 Freeze Flag (03.104) is 0 then the first suitable edge produced by the trigger source causes the freeze position to be stored and the F1 Freeze Flag (03.104) to be set to 1. If further suitable edges are produced by the trigger source the freeze position is updated with the current position.

3: Falling All
As for Rising All, but the falling edge is used to trigger freeze events.

Parameter | 03.102 F1 Freeze Position Source
--- | ---
Short description | Defines the source position for the F1 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | P1
1 | P2
2 | Time

F1 Freeze Position Source (03.102) defines the source for the F1 freeze system as follows:

P1 or P2
When a freeze event occurs, the position from the relevant position feedback interface within the drive (i.e. P1 or P2), including the effect of the marker (see P1 Marker Mode (03.031)), is stored and can be accessed as a 32 bit normalised value in F1 Normalised Freeze Position (03.103). For a digital incremental source (AB, FD, FR, AB Servo, FD Servo or FR Servo) the position is captured at the freeze event using a hardware system. For a resolver the freeze position is the position at the last 250us sample point. For all other position feedback devices the time of the freeze event is captured with hardware and then interpolation, based on the change of position during the previous nominal 250us period, is used to estimate the position at the freeze event.

Time
The time of the freeze event is stored with respect to the last datum used by the position feedback system and option modules fitted to the drive. These datum events occur at a nominal rate of 250us, but if the drive timing is being synchronised by the comms system in an option module then the actual timing may vary slightly depending on the accuracy of the clock providing the sysnchronisation. The time stored in F1 Normalised Freeze Position (03.103) is given as a proportion of the nominal 250us time period where 65536 corresponds to one nomial 250us time period. Note that the value may be positive or negative. Positive values give the time of an event that occured after the last datum, but before the freeze information is processed. Negative values give the time of an event that occurred before the datum, but after the previous time when the freeze information was processed. The time of the freeze event could be used, for example, to determine the value of a virtual position being generated within an option module at the freeze event. The calculated value would only be meaningful if the freeze information is used during the period between the position datum before and after the freeze event, because the time is related to the datum before the freeze information is made available.

Parameter | 03.103 F1 Normalised Freeze Position
--- | ---
Short description | Displays the normalised position from the F1 freeze system
Mode | RFC‑S
Minimum | -2147483648 | Maximum | 2147483647
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See F1 Freeze Position Source (03.102).

Parameter | 03.104 F1 Freeze Flag
--- | ---
Short description | Displays when a freeze event occurs from the F1 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default |  | Units |
Type | 1 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RW, ND, NC, PT

The freeze flag is set when a freeze event occurs. If 0 is written to F1 Freeze Flag (03.104) the freeze flag is cleared.

Parameter | 03.105 F2 Freeze Trigger Source
--- | ---
Short description | Used to select the source that generates trigger events for the F2 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 6
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Digital Input 4
1 | Digital Input 5
2 | P1 Marker
3 | P2 Marker
4 | Common
5 | P1 Zero
6 | P2 Zero

F2 Freeze Trigger Source (03.105) is used to select the source that generates trigger events for the F2 freeze system.

0, 1: Dig I/O 4, Dig I/O 5
Digital I/O 4 or Digital I/O 5 on the drive can be used as trigger sources. If the digital I/O is set up as an input, then trigger events will be produced on the relevant edge of the input signal. If the digital I/O is set up as an output, then trigger events will be produced on the relevant edge of the output signal.

2, 3: Z1, Z2
Z1 selects the P1 position feedback interface marker input as the trigger source and Z2 selects the P2 position feedback interface marker input as the trigger source. No trigger events will be produced unless the selected maker input is available.

4: Common
The output of the common freeze line is selected. If the output of the drive common freeze system is enabled (Bit 3 of Common Freeze Mode (03.112) = 1) then the drive common freeze system provides the freeze event triggers. If the output of the drive common freeze system is disabled the option module freeze line provides the freeze event triggers.

5, 6: P1 Zero, P2 Zero
A freeze event is triggered when the turns for the respective position feedback interface change (i.e. the feedback position passes through zero in either direction). The freeze position stored in F1 Normalised Freeze Position (03.103) or F2 Normalised Freeze Position (03.108) will include the turns associated with the zero position whichever direction the position changes. For example if the turns change from 4 to 5 or 5 to 4 the turns value stored is 5. This mode can be used as a substitute for a physical marker with a position device that does not have one to trigger an event to occur at the zero position of the feeback device. For example, it can be used with the AMC to start a CAM at the zero position of the feedback device. It should be noted that if P1 Zero is selected as the trigger source then F1 Freeze Position Source (03.102) has no effect and P1 is always used as the freeze position source. If P2 Zero is selected as the trigger source then F1 Freeze Position Source (03.102) has no effect and P2 is always used as the freeze position source. This is because these freeze trigger sources are only intended to capture the zero position of the device being used to give the zero position trigger event.

Parameter | 03.106 F2 Freeze Mode
--- | ---
Short description | Defines the mode for the F2 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 3
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Rising 1st
1 | Falling 1st
2 | Rising all
3 | Falling all

0: Rising 1st
Freeze events are produced on the rising edge of the freeze trigger source. If the F2 Freeze Flag (03.109) is 0 then the first suitable edge produced by the trigger source causes the freeze position to be stored and the F2 Freeze Flag (03.109) to be set to 1. No further freeze events are possible until the F2 Freeze Flag (03.109) has been cleared by the user.

1: Falling 1st
As for Rising 1st, but the falling edge is used to trigger freeze events.

2: Rising All
Freeze events are produced on the rising edge of the freeze trigger source. If the F2 Freeze Flag (03.109) is 0 then the first suitable edge produced by the trigger source causes the freeze position to be stored and the F2 Freeze Flag (03.109) to be set to 1. If further suitable edges are produced by the trigger source the freeze position is updated with the current position.

3: Falling All
As for Rising All, but the falling edge is used to trigger freeze events.

Parameter | 03.107 F2 Freeze Position Source
--- | ---
Short description | Defines the source position for the F2 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | P1
1 | P2
2 | Time

F2 Freeze Position Source (03.107) defines the source for the F1 freeze system as follows:

P1 or P2
When a freeze event occurs, the position from the relevant position feedback interface within the drive (i.e. P1 or P2), including the effect of the marker (see P1 Marker Mode (03.031)), is stored and can be accessed as a 32 bit normalised value in F2 Normalised Freeze Position (03.108). For a digital incremental source (AB, FD, FR, AB Servo, FD Servo or FR Servo) the position is captured at the freeze event using a hardware system. For a resolver the freeze position is the position at the last 250us sample point. For all other position feedback devices the time of the freeze event is captured with hardware and then interpolation, based on the change of position during the previous nominal 250us period, is used to estimate the position at the freeze event.

Time
The time of the freeze event is stored with respect to the last datum used by the position feedback system and option modules fitted to the drive. These datum events occur at a nominal rate of 250us, but if the drive timing is being synchronised by the comms system in an option module then the actual timing may vary slightly depending on the accuracy of the clock providing the synchronisation. The time stored in F2 Normalised Freeze Position (03.108) is given as a proportion of the nominal 250us time period where 65536 corresponds to one nomial 250us time period. Note that the value may be positive or negative. Positive values give the time of an event that occured after the last datum, but before the freeze information is processed. Negative values give the time of an event that occurred before the datum, but after the previous time when the freeze information was processed. The time of the freeze event could be used, for example, to determine the value of a virtual position being generated within an option module at the freeze event. The calculated value would only be meaningful if the freeze information is used during the period between the position datum before and after the freeze event, because the time is related to the datum before the freeze information is made available.

Parameter | 03.108 F2 Normalised Freeze Position
--- | ---
Short description | Displays the normalised position from the F2 freeze system
Mode | RFC‑S
Minimum | -2147483648 | Maximum | 2147483647
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See F2 Freeze Position Source (03.107).

Parameter | 03.109 F2 Freeze Flag
--- | ---
Short description | Displays when a freeze event occurs from the F2 freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default |  | Units |
Type | 1 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RW, ND, NC, PT

The freeze flag is set when a freeze event occurs. If 0 is written to F2 Freeze Flag (03.109) the freeze flag is cleared.

Parameter | 03.110 Common Freeze Source 1
--- | ---
Short description | Defines source 1 for the common freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 4
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Digital Input 4
1 | Digital Input 5
2 | P1 Marker
3 | P2 Marker
4 | Disabled

See F1 Freeze Trigger Source (03.100) or F2 Freeze Trigger Source (03.105). It should be noted that if the Disabled option is selected then the input is set to a one.

Parameter | 03.111 Common Freeze Source 2
--- | ---
Short description | Defines source 2 for the common freeze system
Mode | RFC‑S
Minimum | 0 | Maximum | 4
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Digital Input 4
1 | Digital Input 5
2 | P1 Marker
3 | P2 Marker
4 | Disabled

See F1 Freeze Trigger Source (03.100) or F2 Freeze Trigger Source (03.105). It should be noted that if the Disabled option is selected then the input is set to a one.

Parameter | 03.112 Common Freeze Mode
--- | ---
Short description | Defines the mode used for the common freeze system
Mode | RFC‑S
Minimum | 0 (Display: 0000) | Maximum | 15 (Display: 1111)
Default | 0 (Display: 0000) | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Binary | Decimal Places | 0
Coding | RW

The common freeze system can be used to logically combine two freeze trigger sources. The switches in the common freeze system are controlled by the bits in Common Freeze Mode (03.112) as defined in the table below.

Bit | Function
0 | Source 1 input invert
1 | Source 2 input invert
2 | Output invert
3 | Output enable

Therefore the value defined bits 2 to 0 can be used to generate various logic functions as given in the table below.

Bits 2 to 0 | Function
0 | Source1 AND Source2
1 | NOT(Source1) AND Source2
2 | Source1 AND NOT(Source2)
3 | Source1 NOR Source2
4 | Source1 NAND Source2
5 | NOT(Source1) NAND Source2
6 | Source1 NAND NOT(Source2)
7 | Source1 OR Source2

Parameter | 03.113 Freeze Input States
--- | ---
Short description | Displays the level of the selected freeze inputs
Mode | RFC‑S
Minimum | 0 (Display: 00) | Maximum | 3 (Display: 11)
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | 4ms write
Display Format | Binary | Decimal Places | 0
Coding | RO, ND, NC, PT

The bits in Freeze Input States (03.113) show the level of the selected freeze trigger inputs. Bit 0 corresponds to F1 freeze input and bit 1 corresponds to F2 freeze input. It should be noted that if the trigger option is P1Zero or P2Zero there is no hardware trigger input, and so the relevant bit is always zero.

Parameter | 03.114 F1 Freeze Sensor Delay
--- | ---
Short description | Used to compensate for the sensor delay for F1 freeze channel.
Mode | RFC‑S
Minimum | 0.0 | Maximum | 250.0
Default | 0.0 | Units | µs
Type | 16 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 1
Coding | RW

Any delay in the sensor used to trigger a freeze event in the drive through freeze channel F1 or F2 will cause the freeze position to advance (give a larger freeze position) in the forward direction or retard (give a smaller freeze position) in the reverse direction compared to the actual physical position. This effect becomes worse as the speed is increased. The error for a rotary device is given by

Freeze Error = (Speed (rpm) / 60) x 2Normalised Position Bits x Sensor Time Delay

Where Normalised Position Bits is the number of bits representing one turn for the position feedback being used. For example Normalised Position Bits = 32 - P1 Normalisation Turns (03.057) if the position feedback is being taken from the drive P1 interface. The Sensor Delay Time also includes delays in the drive electronics, but these are less than 500ns for either the digital I/O or the marker inputs. The delay compensation feature is only provided under the following conditions, where examples are given for Freeze Channel F1.

1. The position source is not set to Time. (F1 Freeze Position Source (03.102) must be set to P1 or P2.)
2. The trigger source is not set to P1 Zero or P2 Zero. (F1 Freeze Trigger Source (03.100) must be set to Digital Input 4, Digital Input 5, P1 Marker, P2 Marker or Common.)
3. The position feedback type must not be Resolver or Commutation Only.

Parameter | 03.115 F2 Freeze Sensor Delay
--- | ---
Short description | Used to compensate for the sensor delay for F2 freeze channel.
Mode | RFC‑S
Minimum | 0.0 | Maximum | 250.0
Default | 0.0 | Units | µs
Type | 16 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 1
Coding | RW

See F1 Freeze Sensor Delay (03.114).

Parameter | 03.118 P1 Thermistor Type
--- | ---
Short description | Defines the thermistor type for the P1 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 5
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text | Description
0 | DIN44082 | Three thermistors in series as specified in DIN44082 standard
1 | KTY84 | KTY84 PTC thermistor
2 | 0.8mA | Any device. Full scale equivalent to a resistance of 5k ohms
3 | Encoder | Comms encoder with resistance limits
4 | PT1000 | PT1000 temperature sensor
5 | Encoder (Temp) | Comms encoder with temperature limits

P1 Thermistor Type (03.118) defines the operating mode of the P1 thermistor input.

P1 Thermistor Type (03.118): All except Encoder [3] and Encoder (Temp) [5]
If the temperature measuring device is connected between the pin 15 of the encoder interface and 0V a current source will pass 0.8mA through the device. The resistance of the device is calculated and displayed in P1 Thermistor Feedback (03.119). The measured resistance can be used to initiate an over-temperature or device short circuit trip. See P1 Thermistor Fault Detection (03.123) for details. If KTY84 or PT1000 are selected the resistance is converted to a temperature and written to P1 Thermistor Temperature (03.122).

P1 Thermistor Type (03.118): Encoder [3], Encoder (Temp) [5]
If an encoder which supports external temperature feedback (i.e. EnDat 2.2 or EnDat 3) is connected to the P1 position feedback interface then it is possible to obtain the measured temperature from the encoder if P1 Thermistor Type (03.118) is set to Encoder [3] or Encoder (Temp) [5]. The temperature is written to P1 Thermistor Temperature (03.122). If Encoder [3] is used, the drive assumes a KTY84 device is connected to the encoder and converts the temperature to an equivalent resistance so that the resistance based thermal-protection system can be used. The converted resistance is written to P1 Thermistor Feedback (03.119). The drive does not check if an external device is connected, but short circuit protection can be selected to detect if the device is not connected because the resistance will appear as zero. If Encoder (Temp) [5] is used, the limits can be specified in degrees Celsius instead. This improves usability and allows any thermistor types supported by the encoder to be used. See P1 Thermistor Fault Detection (03.123) for details on the resistance and temperature based thermal protection system.

Parameter | 03.119 P1 Thermistor Feedback
--- | ---
Short description | Displays the resistance of the thermistor on the P1 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 5000
Default |  | Units | Ω
Type | 16 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See P1 Thermistor Type (03.118).

Parameter | 03.120 P1 Thermistor Trip Threshold
--- | ---
Short description | Defines the thermistor trip threshold for the P1 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 5000
Default | 3300 | Units | Ω
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See P1 Thermistor Fault Detection (03.123).

Parameter | 03.121 P1 Thermistor Reset Threshold
--- | ---
Short description | Defines the thermistor reset threshold for the P1 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 5000
Default | 1800 | Units | Ω
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See P1 Thermistor Fault Detection (03.123).

Parameter | 03.122 P1 Thermistor Temperature
--- | ---
Short description | Displays the temperature of the device based on the resistance to temperature characteristic for the specified device
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default |  | Units | °C
Type | 16 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

See P1 Thermistor Type (03.118).

Parameter | 03.123 P1 Thermistor Fault Detection
--- | ---
Short description | Defines the fault detection for the P1 thermistor input
Mode | RFC‑S
Minimum | 0 | Maximum | 2
Default | 1 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text | Description
0 | None | No detection active
1 | Temperature | Over temperature detection
2 | Temp or Short | Over temperature and short circuit detection

Defines the fault detection mode for the P1 thermistor input.

P1 Thermistor Type (03.118): All except Encoder (Temp) [5]
Resistance limits are used for these devices. If over temperature detection is enabled a Thermistor.004 trip is initiated if P1 Thermistor Feedback (03.119) is above the resistance defined by P1 Thermistor Trip Threshold (03.120). The trip cannot be reset until P1 Thermistor Feedback (03.119) is below P1 Thermistor Reset Threshold (03.121). If short circuit detection is enabled then a Th Short Circuit.004 is initiated if P1 Thermistor Feedback (03.119) is below 50 ohms.

P1 Thermistor Type (03.118): Encoder (Temp) [5]
Temperature limits are used for this device. If over temperature detection is enabled a Thermistor.004 trip is initiated if P1 Thermistor Temperature (03.122) is above the temperature defined by P1 Thermistor Trip Temperature (03.124). The trip cannot be reset until P1 Thermistor Temperature (03.122) is below P1 Thermistor Reset Temperature (03.125). If short circuit detection is enabled then a Th Short Circuit.004 is initiated if P1 Thermistor Temperature (03.122) is at -50°C. This assumes a PTC thermistor is always used and the thermistor type has an equivalent temperature of less than -50°C when the resistance is close to 0 ohms.

Parameter | 03.124 P1 Thermistor Trip Temperature
--- | ---
Short description | Defines the thermistor trip temperature for the P1 interface
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default | 145 | Units | °C
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See P1 Thermistor Fault Detection (03.123).

Parameter | 03.125 P1 Thermistor Reset Temperature
--- | ---
Short description | Defines the thermistor reset temperature for the P1 interface
Mode | RFC‑S
Minimum | -50 | Maximum | 300
Default | 60 | Units | °C
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See P1 Thermistor Fault Detection (03.123).

Parameter | 03.127 P2 Speed Feedback
--- | ---
Short description | Displays the speed feedback from the P2 interface
Mode | RFC‑S
Minimum | −VM_SPEED | Maximum | VM_SPEED
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, VM, ND, NC, PT

Provided the set-up parameters for the position feedback device connected to the drive P2 position interface are correct P2 Speed Feedback (03.127) shows the speed derived from the feedback. The speed is given in mm/s if P2 Linear Feedback Select (03.151) = 1 and Linear Speed Select (01.055) = 1, otherwise it is given in rpm. The value shown is measured over a 16ms sliding window period, and so the ripple in this value is as defined for Speed Feedback (03.002).

Parameter | 03.128 P2 Revolution/Pole Pitch Counter
--- | ---
Short description | Displays the revolution/pole pitch counter from the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default |  | Units |
Type | 16 Bit Power Down Save | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT, BU

P2 Revolution/Pole Pitch Counter (03.128), P2 Position (03.129) and P2 Fine Position (03.130) combined give the encoder position with a resolution of 1/232 of a revolution/pole pitch as a 48 bit number. If a rotary position feedback device is being used (P2 Linear Feedback Select (03.151) = 0) then these quantities relate directly to the rotary position of the feedback device. If a linear feedback device is used then one revolution or pole pitch relates to the distance given by P2 Pole Pair Pitch (03.155).

See P1 Revolution/Pole Pitch Counter (03.028) for more information.

Parameter | 03.129 P2 Position
--- | ---
Short description | Displays the position feedback from the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default |  | Units |
Type | 16 Bit Power Down Save | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT, BU

See P2 Revolution/Pole Pitch Counter (03.128).

Parameter | 03.130 P2 Fine Position
--- | ---
Short description | Displays the fine position from the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default |  | Units |
Type | 16 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT, BU

See P2 Revolution/Pole Pitch Counter (03.128).

Parameter | 03.131 P2 Marker Mode
--- | ---
Short description | Defines the marker mode for the P2 interface
Mode | RFC‑S
Minimum | 0 (Display: 00000) | Maximum | 31 (Display: 11111)
Default | 4 (Display: 00100) | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Binary | Decimal Places | 0
Coding | RW

P2 Device type (03.138): AB, FD, FR
Each position feedback device produces incremental signals which are counted in hardware. If P2 Marker Mode (03.131) = 0 the following occurs when a marker event is produced by the Z1 input:

1. P2 Position (03.129) and P2 Fine Position (03.130) are reset to zero.
2. The bits in P2 Normalised Position (03.158) related to P2 Position (03.129) and P2 Fine Position (03.130) are reset to zero
3. P2 Marker Flag (03.132) is set to one.

The marker is a hardware function, and so the position appears as though it is reset at the marker event time even if this is between control system sample points. It should be noted that the marker event occurs on the rising edge of the marker pulse if the position change over the last sample was positive or on the falling edge if the position change over the last sample was negative. This ensures that the marker event occurs at the same physical location for either direction of rotation.

The action taken when a marker event occurs can be modified by setting the bits of P2 Marker Mode (03.131) as described in the table below.

Bit | Effect of setting bit to one
0 | No action is taken unless the marker flag is zero before the marker event occurs
1 | P2 Revolution/Pole Pitch Counter (03.128) and the whole of P2 Normalised Position (03.158) are also set to zero on a marker event
2 | P2 Revolution/Pole Pitch Counter (03.128), P2 Position (03.129), P2 Fine Position (03.130) and the related part of P2 Normalised Position (03.158) are not reset. (This overrides bit 1.) P2 Normalised Position (03.158) is transferred to P2 Normalised Marker Position (03.159) and P2 Marker Flag (03.132) is set to one.
3 | This bit in has not effect.
4 | Disables the marker function. The marker is enabled when this bit is left at its default of zero.

The marker input can be used for a standard type marker function or alternatively it can be used as an additional freeze input for the P1 position feedback interface.

P2 Device type (03.138): Any other device type
The marker function cannot be used and P2 Marker Mode (03.131) has no effect.

Parameter | 03.132 P2 Marker Flag
--- | ---
Short description | Indicates when a marker event occurs
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RW, NC

P2 Marker Flag (03.132) is set to one when a marker event occurs. The flag must be cleared by the user.

Parameter | 03.133 P2 Rotary Turns Bits
--- | ---
Short description | Defines the number of rotary turns bit for the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 16
Default | 16 | Units |
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Rotary Turns Bits (03.133) only has any effect if the position feedback interface is being used with a rotary device (i.e. P2 Linear Feedback Select (03.151) = 0).

P2 Device type (03.138): EnDat, BISS, SSI
P2 Rotary Turns Bits (03.133) is used to determine the number of bits within the comms messages from the position feedback device that represent turns. For a single turn encoder P2 Rotary Turns Bits (03.133) must be set to zero. It should be noted that some SSI encoders include leading zeros before the turns information and in this case the number of turns bits should include the leading zeros. The most significant bits in P1 Revolution/Pole Pitch Counter (03.028) that are not included in the turns information provided by the encoder comms are held at zero. If P2 Rotary Turns Bits (03.133) = 0 (single turn encoder) the whole of P2 Revolution/Pole Pitch Counter (03.128) is held at zero.

P2 Device type (03.138): Any other device type
It is sometimes desirable to mask off the most significant bits of P2 Revolution/Pole Pitch Counter (03.128), but this does not have to be done for the drive to function correctly. If P2 Rotary Turns Bits (03.133) = 0 the whole of P2 Revolution/Pole Pitch Counter (03.128) is held at zero. If P2 Rotary Turns Bits (03.133) has any other value it indicates the number of bits in P2 Revolution/Pole Pitch Counter (03.128) that are not held at zero. For example, if P2 Rotary Turns Bits (03.133) = 5, then P2 Revolution/Pole Pitch Counter (03.128) counts up to 31 before being reset.

Parameter | 03.134 P2 Rotary Lines Per Revolution
--- | ---
Short description | Defines the number of rotary lines per revolution for the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 100000
Default | 4096 | Units |
Type | 32 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Rotary Lines Per Revolution (03.134) only has any effect if the position feedback interface is being used with a rotary device (i.e. P2 Linear Feedback Select (03.151) = 0).

P2 Device type (03.138): AB
P2 Rotary Lines Per Revolution (03.134) should be set to the number of lines per revolution for the encoder connected to the P1 position feedback interface.

P2 Device type (03.138): FD, FR
P2 Rotary Lines Per Revolution (03.134) should be set to the number of lines per revolution for the encoder connected to the P1 position feedback interface multiplied by 2.

P2 Device type (03.138): Any other device type
P2 Rotary Lines Per Revolution (03.134) has no effect.

Parameter | 03.135 P2 Comms Bits
--- | ---
Short description | Defines the total number of bits of position information in the comms message from the encoder on the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 48
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Device type (03.138): EnDat, SSI, BiSS
P2 Comms Bits (03.135) should be set to the total number of bits of position information in the comms message from the encoder. If SSI communications is being used this should include any leading or trailing zeros and the power supply alarm bit if present.

P2 Device type (03.138): Any other device type
P2 Comms Bits (03.135) has no effect.

Parameter | 03.137 P2 Comms Baud Rate
--- | ---
Short description | Defines the baud rate used for encoder communications
Mode | RFC‑S
Minimum | 0 | Maximum | 8
Default | 2 | Units | Baud
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | 100k
1 | 200k
2 | 300k
3 | 400k
4 | 500k
5 | 1M
6 | 1.5M
7 | 2M
8 | 4M

P2 Comms Baud Rate (03.137) defines the baud rate used for encoder communications. Restrictions are applied to the baud rate for different feedback devices, and so the baud rate may be different to the parameter value.

P2 Device type (03.138): EnDat, BiSS, SSI
Any baud rate that is within the range specified for the encoder may be used. The line delay is measured during initialisation, and used to compensate this delay during communications with the encoder. Therefore there is no timing based restriction on the length of the cable between the position feedback interface and the encoder. However, care should be taken to ensure that the wiring arrangement and the type of cable used are suitable for the selected baud rate and the distance between the position interface and the encoder. See P2 Low Speed Update Rate Active (03.163) for more details on timing restrictions related to the drive sample times.

The drive hardware can malfunction when a BiSS encoder is used and the line delay time is an integral multiple of the clock period. To avoid this problem the drive will automatically increase the baud rate to minimise the effect. This does not affect any parameters, and so the only thing that is visible is that the baud rate is higher than the setting in this parameter. The maximum reduction of the clock period is 62.5ns. For example if 4M Baud is selected the baud rate could be increased up to 5.33M Baud.

P2 Device type (03.138): Any other device
P2 Comms Baud Rate (03.137) has no effect.

Parameter | 03.138 P2 Device type
--- | ---
Short description | Set this to the feedback device type connected to the P2 position interface
Mode | RFC‑S
Minimum | 0 | Maximum | 6
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | None
1 | AB
2 | FD
3 | FR
4 | EnDat
5 | SSI
6 | BiSS

If P2 Device type (03.138) = Disabled, the P2 position feedback interface is disabled and does not provide any position feedback.

See P1 Device Type (03.038) for more information on the different position feedback device types.

Parameter | 03.140 P2 Error Detection Level
--- | ---
Short description | Used to enable or disable position feedback trip functions
Mode | RFC‑S
Minimum | 0 (Display: 00000) | Maximum | 31 (Display: 11111)
Default | 1 (Display: 00001) | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Binary | Decimal Places | 0
Coding | RW

This parameter can be used to enable or disable position feedback trip functions as follows:

Bit | Function
0 | Not used with the P2 position interface.
1 | Not used with the P2 position interface.
2 | Enable SSI power supply alarm bit monitor (indicated by trip Encoder 6).
3 | Disable trips Encoder 1 to Encoder 6.
4 | Disable trip Encoder 7.

Bits 3 and 4 do not prevent the device from becoming un-initialised. The trip is suppressed, but the device is still un-initialised and this is indicated by the appropriate bit for the position feedback interface in Position Feedback Initialized (03.076).

Encoder trips
The following table shows trips that can be initiated that are related to the position feedback interface P2. The sub-trip number is 2 for the drive P2 position feedback interface.

Drive trip | Encoders | Reason for error
Encoder 4 | EnDat, BISS | Comms timeout
Encoder 5 | EnDat, BISS | Checksum/CRC error
SSI | Not ready at start of position transfer (i.e. data input not one)
Encoder 6 | EnDat, BiSS | The encoder has indicated an error
SSI | Power supply alarm bit active
Encoder 7 | EnDat, BiSS, SSI | An attempt has been made to enable the drive, but a position feedback device is not initialised
Encoder 8 | EnDat, SSI, BiSS | Maximum Switching Frequency (05.018), P2 Device type (03.138), P2 Comms Bits (03.135), P2 Comms Baud Rate (03.137), P2 Calculation Time (03.160), P2 Recovery Time (03.161), P2 Line Delay Time (03.162) and P2 User Comms Enable (03.167) are used to determine the time taken for the communications exchange with the encoder. If this time exceeds 250μs an Encoder 8 trip is initiated.
Encoder 9 | All | Speed feedback selected from an option slot that does not have a position feedback category option module fitted
Phasing Error | All | Incorrect encoder phasing 1
Encoder 12 | BiSS | The encoder could not be identified during auto-configuration

1. Incorrect encoder phasing is detected if the motor reaches half of the speed defined by VM_SPEED_FREQ_REF[MAX] and the phasing error is large enough for the motor to accelerate uncontrollably.

Wire-break detection
It may be important to detect a break in the connections between the drive and the position feedback device. This feature is provided for most position feedback devices either directly or indirectly as listed below.

Device | Detection method | Trip produced
AB, FD, FR | There is no wire break detection of the A2, B2, and Z2 signals on the P2 position interface. | None
EnDat, BiSS | Wire break in the comms link is detected by a CRC or timeout error. | Encoder 4, Encoder 5
SSI | Wire break detection in the comms is difficult with these devices. However, if power supply alaram bit monitoring is enabled the drive will be looking for a one at the start of the message and a zero to indicate that the power supply is okay. If the clock stops or the data line is disconnected the data input to the drive may stay in one state or the other and cause a trip. | Encoder 5, Encoder 6

Parameter | 03.141 P2 Auto-configuration Select
--- | ---
Short description | Set this parameter to enable auto-configuration of EnDat and BiSS feedback devices
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 1 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Disabled
1 | Enabled

P2 Device type (03.138): EnDat
If auto-configuration is enabled (i.e. P2 Auto-configuration Select (03.141) = 1) then during position feedback initialisation the encoder is interrogated to determine whether the encoder is a rotary or linear encoder and P2 Linear Feedback Select (03.151) is set up appropriately. Then the following parameters are set up based on information from the encoder:

Rotary | Linear
P2 Rotary Turns Bits (03.133) | P2 Linear Comms Pitch (03.152)
P2 Rotary Lines Per Revolution (03.134) | P2 Linear Line Pitch (03.153)
P2 Comms Bits (03.135) | P2 Comms Bits (03.135)
| P2 Linear Comms And Line Pitch Units (03.154)

The following actions are also taken to set up the timing for the encoder.

Comms Protocol | Actions taken
EnDat 2.1 | P2 Calculation Time (03.160) = From the encoder P2 Recovery Time (03.161) = 30μs Line delay measured and result written to P2 Line Delay Time (03.162)
EnDat 2.2 | P2 Calculation Time (03.160) = From the encoder P2 Recovery Time (03.161) = 4μs and the recovery time within the encoder is set up to the shortest value of 3.75μs if the P2 Comms Baud Rate (03.137) is 1M or more.Line delay measured and result written to P2 Line Delay Time (03.162)

Once these parameters have been set up it should be possible for the drive to operate correctly with the encoder. Auto-configuration occurs as part of the position interface initialisation if selected, and so if the auto-configuration fails (i.e. communications cannot be established) then initialisation will not be completed. If initialisation has not been completed successfully the drive cannot be enabled (see Enable Conditions (06.010)).

If auto-configuration is disabled ((i.e. P2 Auto-configuration Select (03.141) = 0) then none of the above actions are carried out except for the line delay measurement.

P2 Device type (03.138): BiSS
If auto-configuration is enabled (i.e. P2 Auto-configuration Select (03.141) = 1) then during position feedback initialisation the standard CRC for BiSS encoders (X6+X+1) is selected by setting P2 Additional Configuration (03.174) to 67000000 and the maximum baud rate is selected by setting P2 Comms Baud Rate (03.137) to 4MBaud. All BiSS encoders should operate with a clock frequency of 10MHz, and so this should be suitable for all devices. If the encoder contains contains a BP3 type EDS (electronic data sheet) as defined in the BiSS specifications then the drive will attempt to use this to set up parameters to allow the encoder to function. For this to work correctly the EDS-bank (Bank 0 Address 65) must be set to the bank containing the start of the EDS (i.e. the common part EDS), Profile ID Byte 1 (Bank 0 Addresses 66) must be define the BP3 profile (i.e. the MS 4 bits are 6) and Profile ID Byte 0 (Bank 0 Address 67) must define the total number of communication bits. The EDS is only used for rotary encoders, and so P2 Linear Feedback Select (03.151) must be zero. The following data from the encoder is used.

Bank | Address | Data | Comments | Action on failure
0 | 66 | Profile-ID Byte 1 | This must define a BP3 profile and so the MS 4 bits must be 6. | The EDS data is not used.
0 | 67 | Profile-ID Byte 0 | Total number of communications bits = P2 Comms Bits (03.135) + Error Bit + Warning Bit + 6 CRC Bits. | If the calculated value for P2 Comms Bits (03.135) > 48 an Encoder 13.25 trip is initiated.
0 | 65 | EDS-Bank | Used to locate the start of the common part of the EDS. |
EDS-Bank | 12 | TBUSY_S | Gives the encoder calculation time in 250ns units. This is converted to microseconds and written to P2 Calculation Time (03.160). | If the calculated value is larger than 20us an Encoder 13.26 trip is initiated.
EDS-Bank + 1 | 8 | EN_TYP | This must be zero indicating a rotary encoder. | If the value is not zero an Encoder 12.2 trip is initiated.
EDS-Bank + 1 | 10 | MT_LEN | This is the number of encoder turns bits and is written to P2 Rotary Turns Bits (03.133). | If the value is larger than 16 an Encoder 13.24 trip is initiated.
EDS-Bank + 1 | 20 | SIP_CNT Byte 3 | These 4 bytes form a 32 bit value that defines the number of signals per revolution for an SC.BiSS encoders and are written to P2 Rotary Lines Per Revolution (03.134). | If the value is larger than 100000 an Encoder 13.21 trip is initiated.
EDS-Bank + 1 | 21 | SIP_CNT Byte 2 |  |
EDS-Bank + 1 | 22 | SIP_CNT Byte 1 |  |
EDS-Bank + 1 | 23 | SIP_CNT Byte 0 |  |

Once the auto-configuration data has been obtained successfully P2 Line Delay Time (03.162) is set to 13us, which is the longest timeout used by any BiSS encoders, and then line delay measurement is carried out to set up P2 Line Delay Time (03.162).

If auto-configuration is disabled ((i.e. P2 Auto-configuration Select (03.141) = 0) then none of the above actions are carried out except for the line delay measurement.

P2 Device type (03.138): All other device types
P2 Auto-configuration Select (03.141) has no effect.

Parameter | 03.142 P2 Feedback Filter
--- | ---
Short description | Defines the time period for a sliding window filter that may be applied to the feedback taken from the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 5
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | Disabled
1 | 1ms
2 | 2ms
3 | 4ms
4 | 8ms
5 | 16ms

P2 Feedback Filter (03.142) defines the time period for a sliding window filter that may be applied to the feedback taken from the drive P2 position feedback interface. This is particularly useful in applications where the drive encoder is used to give speed feedback for the speed controller and where the load includes a high inertia, and so the speed controller gains are very high. Under these conditions, without a filter on the feedback, it is possible for the speed loop output to change constantly from one current limit to the other and lock the integral term of the speed controller.

Parameter | 03.143 P2 Maximum Reference
--- | ---
Short description | Defines the maximum speed reference from the P2 interface
Mode | RFC‑S
Minimum | 0 | Maximum | 33000
Default | 3000 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, BU

The speed feedback from the drive P2 position feedback interface can be used as a source to control a parameter. The speed feedback is scaled to give a value as a percentage of P2 Maximum Reference (03.143) in 0.1% units which is displayed in P2 Reference (03.145). The value is then scaled by the P2 Reference Scaling (03.144) and then routed to the destination defined by P2 Reference Destination (03.146).

Normally the destination is updated every 4ms, but if the destination is the Hard Speed Reference (03.022), P2 Maximum Reference (03.143) = VM_SPEED_FREQ_REF[MAX] and P2 Reference Scaling (03.144) = 1.000 it is updated every 250μs. Although the hard speed reference is updated every 250μs internally a value in rpm or mm/s is written to Hard Speed Reference (03.022) every 4ms for indication only. It should be noted that if the fast update method is used the resolution of the speed feedback devived from the position feedback device defines the resolution of the hard speed reference and that any ripple on the feedback will be present on the hard speed reference (see Speed Feedback (03.002)).

Parameter | 03.144 P2 Reference Scaling
--- | ---
Short description | Defines the scaling applied to the P2 reference
Mode | RFC‑S
Minimum | 0.000 | Maximum | 4.000
Default | 1.000 | Units |
Type | 16 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 3
Coding | RW

See P2 Maximum Reference (03.143).

Parameter | 03.145 P2 Reference
--- | ---
Short description | Displays the value in P2 reference
Mode | RFC‑S
Minimum | -100.0 | Maximum | 100.0
Default |  | Units | %
Type | 16 Bit Volatile | Update Rate | 4ms write
Display Format | Standard | Decimal Places | 1
Coding | RO, FI, ND, NC, PT

See P2 Maximum Reference (03.143).

Parameter | 03.146 P2 Reference Destination
--- | ---
Short description | Defines the destination parameter for P2 reference
Mode | RFC‑S
Minimum | 0.000 | Maximum | 59.999
Default | 0.000 | Units |
Type | 16 Bit User Save | Update Rate | Drive reset read
Display Format | Menu Param Numeric | Decimal Places | 3
Coding | RW, DE, PT, BU

See P2 Maximum Reference (03.143).

Parameter | 03.147 P2 SSI Incremental Mode
--- | ---
Short description | Set to 1 to enable SSI incremental mode
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Device type (03.138): SSI
If P2 SSI Incremental Mode (03.147) = 0 the complete absolute position is read at each sample. Care should be taken when using this mode as some unwanted effects can occur when the encoder passes through the boundary between its maximum position and zero. In this mode the encoder can be used for motor control provided at least 6 bits of turns information are provided by the encoder otherwise an over speed trip will be produced as the position passes over the maximum position to zero boundary. P2 Normalised Position (03.158) can be used for position control over this boundary provided the normalised turns bits are set up so that the normalised positions do not contain turns information that is not available from the encoder. As the SSI format does not include any error checking it is not possible to detect if the position data has been corrupted by noise. The benefit of using the absolute position directly from an SSI encoder is that even if the encoder communications are disturbed by noise and position errors occur, the position will always recover the correct position after the disturbance has ended.

If P2 SSI Incremental Mode (03.147) = 1 the absolute position is only taken from the encoder during initialisation. The change of position over each sample is then accumulated to determine the position. This method always gives 16 bits of turns information that can always be used without jumps in position whatever value is used as the turns bits for normalisation. If noise corrupts the data from an SSI encoder it is possible to have apparent large change of position, and this can result in the turns information becoming and remaining corrupted until the encoder is re-initialised.

If an SSI encoder is used, but is not powered from the drive, and the encoder is powered up after the drive, it is possible that the first change of position detected could be large enough to cause the problems described above. This can be avoided if the encoder interface is initialised with Initialise Position Feedback (03.075) after the encoder has powered up. If the encoder includes a power supply alarm bit, the power supply monitor should be enabled. This will ensure that the drive remains tripped until the encoder is powered up and the action of resetting the trip will reinitialise the encoder interface.

P2 Device type (03.138): All other device types
P2 SSI Incremental Mode (03.147) has no effect.

Parameter | 03.148 P2 SSI Binary Mode
--- | ---
Short description | Set to 1 to enable SSI binary mode
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Device type (03.138): SSI
SSI encoders normally use Gray code data format. However, some encoders use binary format which may be selected by setting P2 SSI Binary Mode (03.148) to one.

P2 Device type (03.138): All other device types
P2 SSI Binary Mode (03.148) has no effect.

Parameter | 03.149 P2 Additional Power-up Delay
--- | ---
Short description | Defines an additional delay for when any attempt is made to communicate to the device P2
Mode | RFC‑S
Minimum | 0.0 | Maximum | 25.0
Default | 0.0 | Units | s
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 1
Coding | RW, BU

When the position feedback is initialised, at power-up or at any other time, a delay is included before the information from the feedback device is used or any attempt is made to communicate with the device. P2 Additional Power-up Delay (03.149) defines an additional delay that is added to the minimum delay. See P1 Additional Power-up Delay (03.049) for the minimum delays for the different position feedback device types.

Parameter | 03.150 P2 Feedback Lock
--- | ---
Short description | Set to 1 to prevent the position feedback parameters for P2 being updated
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

If P2 Feedback Lock (03.150) = 1 then P2 Revolution/Pole Pitch Counter (03.128), P2 Position (03.129) and P2 Fine Position (03.130) are not updated. If P2 Feedback Lock (03.150) = 0 then these parameters are updated normally.

Parameter | 03.151 P2 Linear Feedback Select
--- | ---
Short description | Set to 1 to configure the P2 interface to operate with a linear position feedback device
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

If P2 Linear Feedback Select (03.151) = 0 then the drive P1 position feedback interface is configured to operate with a rotary position feedback device. P2 Rotary Turns Bits (03.133) and P2 Rotary Lines Per Revolution (03.134) should be used to set up the position feedback interface.

If P2 Linear Feedback Select (03.151) = 1 then the position feedback interface is configured to operate with a linear position feedback device. P2 Linear Comms Pitch (03.152) and P2 Linear Line Pitch (03.153) should be used to set up the position feedback interface.

Parameter | 03.152 P2 Linear Comms Pitch
--- | ---
Short description | Defines the distance covered by the least significant bit of the position information in a comms message from a linear encoder
Mode | RFC‑S
Minimum | 0.001 | Maximum | 100.000
Default | 0.001 | Units |
Type | 32 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 3
Coding | RW

P2 Device type (03.138): EnDat, SSI, BiSS
P2 Linear Comms Pitch (03.152) is used to define the distance covered by the least significant bit of the position information in a comms message from a linear encoder. The units used by this parameter are defined by P2 Linear Comms And Line Pitch Units (03.154).

P2 Device type (03.138): Any other device
P2 Linear Comms Pitch (03.152) has no effect.

Parameter | 03.153 P2 Linear Line Pitch
--- | ---
Short description | Defines the linear line pitch for device P2
Mode | RFC‑S
Minimum | 0.001 | Maximum | 100.000
Default | 0.001 | Units |
Type | 32 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 3
Coding | RW

P2 Linear Line Pitch (03.153) only has any effect if the position feedback interface is being used with a linear device (i.e. P2 Linear Feedback Select (03.151) = 1) and should be used to define the distances listed below for each type of device. The units used by this parameter are defined by P2 Linear Comms And Line Pitch Units (03.154).

P2 Device type (03.138): AB
P2 Linear Line Pitch (03.153) should be set to the distance covered by one line period on the encoder.

P2 Device type (03.138): FD, FR
P2 Linear Line Pitch (03.153) should be set to the distance covered by two line periods on the encoder.

P2 Device type (03.138): Any other device
P2 Linear Line Pitch (03.153) has no effect.

Parameter | 03.154 P2 Linear Comms And Line Pitch Units
--- | ---
Short description | Defines the linear units in either millimetres or micrometres
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, TE

Value | Text
0 | millimetres
1 | micrometres

P2 Linear Comms And Line Pitch Units (03.154) defines the units used by P2 Linear Comms Pitch (03.152) and P2 Linear Line Pitch (03.153) in millimetres or micrometres.

Parameter | 03.155 P2 Pole Pair Pitch
--- | ---
Short description | Defines the change of position for one electrical revolution of the drive output with a linear position device.
Mode | RFC‑S
Minimum | 0.01 | Maximum | 1000.00
Default | 10.00 | Units | mm
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 2
Coding | RW

P2 Pole Pair Pitch (03.155) gives the distance equivalent to one electrical revolution when linear position feedback is used. See P1 Pole Pair Pitch (03.055) for more detail.

Parameter | 03.156 P2 Feedback Reverse
--- | ---
Short description | Set to 1 to reverse the direction of the position feedback
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

If P2 Feedback Reverse (03.156) = 1 the position feedback is negated. This can be used to reverse the direction of the position feedback.

Parameter | 03.157 P2 Normalisation Turns
--- | ---
Short description | Defines the number of turns bits included in the normalisation parameters
Mode | RFC‑S
Minimum | 0 | Maximum | 16
Default | 16 | Units |
Type | 8 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Normalisation Turns (03.157) defines the number of turns bits included in the following parameters. See P1 Normalisation Turns (03.057) for more information.

P2 Normalised Position (03.158)
P2 Normalised Marker Position (03.159)
F1 Normalised Freeze Position (03.103) if P2 is the source position for freeze function F1
F2 Normalised Freeze Position (03.108) if P2 is the source position for freeze function F2

Parameter | 03.158 P2 Normalised Position
--- | ---
Short description | Displays the position taken from the position feedback device including the effect of the marker function
Mode | RFC‑S
Minimum | -2147483648 | Maximum | 2147483647
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P2 Normalised Position (03.158) is the position taken from the position feedback device including the effect of the marker function. See P2 Normalisation Turns (03.157) for details of the format.

Parameter | 03.159 P2 Normalised Marker Position
--- | ---
Short description | Displays the normalised position at the last marker event
Mode | RFC‑S
Minimum | -2147483648 | Maximum | 2147483647
Default |  | Units |
Type | 32 Bit Volatile | Update Rate | 250µs write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P2 Normalised Marker Position (03.159) is the value P2 Normalised Position (03.158) at the last marker event provided bit 2 of P2 Marker Mode (03.131) is set to 1. See P2 Marker Mode (03.131) for more details.

Parameter | 03.160 P2 Calculation Time
--- | ---
Short description | Defines the time from the first edge of the clock signal from the position feedback interface until the encoder has calculated the position and is ready to return this information
Mode | RFC‑S
Minimum | 0 | Maximum | 20
Default | 5 | Units | µs
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Device type (03.138): EnDat
P2 Calculation Time (03.160) is the time from the first edge of the clock signal from the position feedback interface until the encoder has calculated the position and is ready to return this information. This is used to calculate the overall time for a message interchange with the encoder. See P2 Low Speed Update Rate Active (03.163) for more details.

P2 Device type (03.138): Any other type of device
P2 Calculation Time (03.160) has no effect.

Parameter | 03.161 P2 Recovery Time
--- | ---
Short description | Defines the time that must be allowed after each message interchange before a new message begins
Mode | RFC‑S
Minimum | 4 | Maximum | 100
Default | 30 | Units | µs
Type | 8 Bit User Save | Update Rate | Background read, auto-configuration write
Display Format | Standard | Decimal Places | 0
Coding | RW

P2 Device type (03.138): EnDat, SSI, BiSS
P2 Recovery Time (03.161) is the time that must be allowed after each message interchange before a new message begins.

P2 Device type (03.138): Any other type of device
P2 Recovery Time (03.161) has no effect.

Parameter | 03.162 P2 Line Delay Time
--- | ---
Short description | Displays the transmission delay between the position feedback interface and the encoder and back again
Mode | RFC‑S
Minimum | 0 | Maximum | 5000
Default |  | Units | ns
Type | 16 Bit User Save | Update Rate | Background read, position feedback initialisation write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P2 Device type (03.138): EnDat, SSI, BiSS
During position feedback initialisation the transmission delay between the position feedback interface and the encoder and back again is measured and stored in P2 Line Delay Time (03.162). This value is then used to compensate for this delay so that the clock/data skew does not prevent the data from the encoder from being read. This means that longer line lengths can be used with these feedback devices provided the correct cable and connection arrangements are used.

P2 Device type (03.138): Any other type of device
P2 Line Delay Time (03.162) is always zero.

Parameter | 03.163 P2 Low Speed Update Rate Active
--- | ---
Short description | Indicates when the low speed update rate is active
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default |  | Units |
Type | 1 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P2 Device type (03.138): EnDat, SSI, BISS
If the position can be sampled in 60μs P2 Low Speed Update Rate Active (03.163) = 0, otherwise P2 Low Speed Update Rate Active (03.163) = 1.

The following parameters are used by the drive to determine the necessary time to obtain the required data from the position feedback device.

P2 Rotary Turns Bits (03.133)
P2 Comms Bits (03.135)
P2 Comms Baud Rate (03.137)
P2 Calculation Time (03.160)
P2 Recovery Time (03.161)
P2 Line Delay Time (03.162)
P2 User Comms Enable (03.167)

See P1 Low Speed Update Rate Active (03.063) for more information on how this time is calculated.

It should be noted that the faster sample rate is only used if the position feedback is being used for motor control (i.e. the drive in operating in RFC-A or RFC-S mode and Motor Control Feedback Select (03.026) = P2 Drive (0)). If this is not the case the communication exchange is completed in 250us and P2 Low Speed Update Rate Active (03.163) = 0.

P2 Device type (03.138): Any other type of device
P2 Low Speed Update Rate Active (03.163) is always zero.

Parameter | 03.164 P2 Encoder Protocol Detected
--- | ---
Short description | Defines which protocol is used with the device P2
Mode | RFC‑S
Minimum | 0 | Maximum | 4
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, TE, ND, NC, PT

Value | Text
0 | None
1 | Hiperface
2 | EnDat2.1
3 | EnDat2.2
4 | BiSS

P2 Encoder Protocol Detected (03.164) shows the encoder comms protocol detected during position feedback initialisation. If P2 Device type (03.138) is set to BiSS then P2 Encoder Protocol Detected (03.164) is set to the appropriate value after successful communication with the encoder during initialisation. If P2 Device type (03.138) is set to EnDat then P2 Encoder Protocol Detected (03.164) is set to the appropriate EnDat protocol after successful communication with the encoder during initialisation. If communications is not successful during initialisation then P2 Encoder Protocol Detected (03.164) is set to 0 (None).

Parameter | 03.167 P2 User Comms Enable
--- | ---
Short description | Enables the use of the user comms parameters to communicate to the encoder connected to P2
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 8 Bit Volatile | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW, NC, PT

If P2 User Comms Enable (03.167) set to a non-zero value it is possible to use P2 User Comms Transmit Register (03.168) and P2 User Comms Receive Register (03.169) to communicate with an encoder that has a Hiperface, EnDat 2.1, EnDat2.2 or BiSS interface. See P1 User Comms Enable (03.067) for a description of how to use these registers.

Parameter | 03.168 P2 User Comms Transmit Register
--- | ---
Short description | Defines the value present in the user comms transmit register
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default | 0 | Units |
Type | 16 Bit Volatile | Update Rate | Background read/write
Display Format | Standard | Decimal Places | 0
Coding | RW, NC, PT, BU

See P2 User Comms Enable (03.167).

Parameter | 03.169 P2 User Comms Receive Register
--- | ---
Short description | Defines the value present in the user comms receive register
Mode | RFC‑S
Minimum | 0 | Maximum | 65535
Default | 0 | Units |
Type | 16 Bit Volatile | Update Rate | Background read/write
Display Format | Standard | Decimal Places | 0
Coding | RW, NC, PT, BU

See P2 User Comms Enable (03.167).

Parameter | 03.171 P2 Error Detected
--- | ---
Short description | Indicates if an error has been detected with the position feedback device connected to the P1 position interface
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default |  | Units |
Type | 1 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, ND, NC, PT

P2 Error Detected (03.171) is set if an error has been detected with the position feedback device connected to the P2 position interface. This parameter is useful if encoder trips have been disabled with P2 Error Detection Level (03.140).

Parameter | 03.172 P2 Status
--- | ---
Short description | Displays the status of the P2 position interface
Mode | RFC‑S
Minimum | 0 | Maximum | 9
Default |  | Units |
Type | 8 Bit Volatile | Update Rate | Background write
Display Format | Standard | Decimal Places | 0
Coding | RO, TE, ND, NC, PT

Value | Text
0 | None
1 | AB
2 | FD
3 | FR
4 | EnDat
5 | SSI
6 | BiSS
7 | EnDat Alt
8 | SSI Alt
9 | BiSS Alt

Priority of the 15-way D-type is assigned in the following order from the highest priority to the lowest.

1. P1 position interface
2. Encoder simulation output
3. P2 position interface

The availability of the P2 position interface on the 15-way D-type on the drive is dependent on type of feedback device selected in P1 Device Type (03.038) and the encoder simulation mode selected in Encoder Simulation Mode (03.088). P2 Status (03.172) shows the status of the P2 position interface depending on the settings in P2 Device type (03.138), P1 Device Type (03.038), and Encoder Simulation Mode (03.088).

0: None
The P2 position interface is not available.

1: AB
2: FD
3: FR
4: EnDat
5: SSI
6: BiSS
The P2 position interface is available. The connections for the P2 position interface are shown below.

P2 Status (03.172) | 15-way D-type connections
1/2 | 3/4 | 5/6 | 7/8 | 9/10 | 11/12
AB |  |  |  | A2 | B2 | Z2
FD |  |  |  | F2 | D2 | Z2
FR |  |  |  | F2 | R2 | Z2
EnDat |  |  |  | D2 | Clk2 | Z2
SSI |  |  |  | D2 | Clk2 | Z2
BiSS |  |  |  | D2 | Clk2 | Z2

7: EnDat Alt
8: SSI Alt
9: BiSS Alt
The P2 position interface is available but uses alternative connections as shown below as connection 7/8 and 9/10 are used by the encoder simulation output.

P2 Status (03.172) | 15-way D-type connections
1/2 | 3/4 | 5/6 | 7/8 | 9/10 | 11/12
EnDat Alt |  |  | D2 | AOut | BOut | Clk2
SSI Alt |  |  | D2 | AOut | BOut | Clk2
BiSS Alt |  |  | D2 | AOut | BOut | Clk2

See the introduction to this menu for more information on the position feedback interfaces.

Parameter | 03.173 P2 Absolute Turns Recovery Enable
--- | ---
Short description | Set to 1 to allow turns information beyond the number of turns bits provided by the position feedback device connected to P2 to be stored on power-down and recovered at next power-up
Mode | RFC‑S
Minimum | 0 | Maximum | 1
Default | 0 | Units |
Type | 1 Bit User Save | Update Rate | Background Read
Display Format | Standard | Decimal Places | 0
Coding | RW

See P1 Absolute Turns Recovery Enable (03.073).

Parameter | 03.174 P2 Additional Configuration
--- | ---
Short description | Provides additional configuration information for the position feedback device not included in the other set-up parameters.
Mode | RFC‑S
Minimum | 0 | Maximum | 511116116
Default | 0 | Units |
Type | 32 Bit User Save | Update Rate | Background read
Display Format | Standard | Decimal Places | 0
Coding | RW

See P1 Additional Configuration (03.074).

Parameter | 03.175 P2 Additional Configuration Information
--- | ---
Short description | Additional information obtained from the device connected to the P2 interface during auto-configuration.
Mode | RFC‑S
Minimum | 0 | Maximum | 2147483647
Default | 0 | Units |
Type | 32 Bit Volatile | Update Rate | Background Write
Display Format | Standard | Decimal Places | 0
Coding | RO, PT

See P1 Additional Configuration Information (03.072).