Process image

The process image (cyclic interface) of an axis is used to connect it to different drive components. In the simplest case, a link is established between the axis and the drive and the necessary links between the process images are made automatically. In individual cases, in particular when unknown hardware components are integrated in the system, these links must be established manually.

Notice The data structures described here form an internal interface between NC drivers and connected drive hardware. This interface is constantly under development and can change in the future.

Drive process image of an axis

Various drive hardware or the corresponding Bus Terminals (+/- 10V, PWM etc.) are connected via the drive process image. Insofar as this hardware is directly supported by the system, no manual configuration is necessary.

Process image 1:

Input data to the drive process image of an axis

NC-In variable

Data type

Description

nDataIn1

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Optional lag error (position control deviation, i.e. target position minus actual position) of the I/O Drive in increments. Exclusively for the operation mode Cyclic Position Mode (e.g. for EtherCAT, SERCOS, CANopen).

This quantity is processed by the NC accordingly and processed mathematically as an "external" lag distance in physical units (e.g. in mm or degrees).

Mapping with:

  • SoE: S-0-0189 Following error
  • CoE: 0x60F4 Following error actual value

nDataIn2

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

reserved

nState1

USINT

Optional status information

e.g.: Drive Error, Drive Enable/Disable, Communication Drive State Machine (e.g. EtherCAT, SERCOS, CANopen, Profibus), Register Communication.

Mapping with

  • SoE: S-0-0135 Drive Statusword
  • CoE: 0x6041 Statusword

nState2

USINT

Additional optional status information.

e.g.: Drive Error, Drive Enable/Disable, Communication Drive State Machine (e.g. EtherCAT, SERCOS, CANopen, Profibus), Register Communication.

Mapping with:

  • SoE: S-0-0135 Drive statusword
  • CoE: 0x6041 Statusword

nState3

USINT

reserved

nState4

USINT

Optional fieldbus-dependent I/O status such as WcState (Working Counter) in the case of EtherCAT or CdlState in the case of Beckhoff Lightbus.

nDataIn3

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Optional actual torque/force value of the I/O Drive in increments.

This variable is processed by the NC accordingly and processed mathematically as "ActTorque" in physical units (e.g. % or A).

nDataIn3[0] mapping with:

  • SoE: S-0-0084 Torque feedback value (2 byte)
  • CoE: 0x6077 Torque actual value (2 byte)

nDataIn4

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

reserved

nDataIn5

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

reserved

nDataIn6

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

reserved

nState5

USINT

Mapping with:

  • CoE: 0x6061 Modes of operation display

nState6

USINT

reserved

nState7

USINT

reserved

nState8

USINT

reserved

nDcOutputTime

DINT

Optional: Used for NC dead time compensation of the drive.

Output data from the drive process image of an axis

NC-Out variable

Data type

Description

nDataOut1

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Current target velocity or current target position in increments

The target velocity or target position of the NC in physical units, e.g. mm or degrees, is mathematically converted back to an incremental value by the NC and transferred to the drive. Overflows of the incremental value are hereby taken into account by the NC in the target position.

Depending on the drive type, a standardization of the target velocity or target position is carried out in increments. If the drive type Universal Drive has been selected, nOutData1 contains the overall velocity (incl. position control part) with sign.

Mapping with:

  • SoE: S-0-0047 Target Position
  • CoE:
    • 0x607A Target position
    • 0x6062 Nominal position,
      Alternative if 0x607A is not available

nDataOut2

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Current target velocity or current target position in increments

The target velocity or target position of the NC in physical units, e.g. mm or degrees, is mathematically converted back to an incremental value by the NC and transferred to the drive. Overflows of the incremental value are hereby taken into account by the NC in the target position.

Depending on the drive type, a standardization of the target velocity or target position is carried out in increments. If the Universal Drive type has been selected, nOutData2 contains the value of the overall velocity (incl. position control part, without sign).

Mapping with:

  • SoE: S-0-0036 Target velocity (4 byte)
  • CoE:
    • 0x60FF Target velocity (4 byte)
    • 0x606B Nominal velocity (4byte),
      Alternative if 0x60FF is not available.
    • 0x6042 Target velocity for velocity mode (for frequency inverter) (2 byte),
      Alternative if 0x60FF and 0x606B are not available.

nCtrl1

USINT

Optional control information

e.g.: Drive Reset, Drive Enable/Disable, Communication Drive State Machine (e.g. EtherCAT, SERCOS, CANopen, Profibus), Register Communication.

Mapping with:

  • SoE: S-0-0134 Master Controlword
  • CoE: 0x6040 Controlword

nCtrl2

USINT

Additional optional control information

Digital direction output of the setpoint generation (corresponds to the sign of the target velocity, hence without position controller)

Digital Outputs Setpoint Generator:
0x41 (0100 0001) = Minus
0x42 (0100 0010) = Plus
0x80 (1000 0000) = Stop
The only exception is the AX2xxx-B200/B900 drive. In this case, communication takes place with the Drive State Machine.

Mapping with

  • SoE: S-0-0134 Master Controlword
  • CoE: 0x6040 Controlword

nCtrl3

USINT

Additional optional control information

Digital direction output or drive stages of the total output (sum of setpoint generation and position controller) Digital Outputs (Setpoint Generator + Position Controller):
0x41 (0100 0001) = Minus
0x42 (0100 0010) = Plus
0x80 (1000 0000) = Stop

nCtrl4

USINT

reserved

nDataOut3

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Current target acceleration (2nd time derivative of target position) in increments. Optionally, it can also contain the current target torque in increments (e.g. from an extended transformation with dynamic model).

The target acceleration and the target torque can be available either individually or as a sum of the individual variables (depending on the parameterization of the output scaling).

The output size is signed.

Mapping with:

  • SoE: S-0-0081 Torque offset (2 byte)
  • CoE: 0x60B2 Torque offset (2 byte)

nDataOut4

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Mapping with:

  • SoE: S-0-0080 Torque command value
    (corresponds to SetTorque multiplied by the output scaling)
  • CoE:
    • 0x6071 Target torque/force (2 byte)
      (corresponds to SetTorque multiplied by the output scaling)
    • 0x6074 Nominal Torque (2 byte),
      Alternative if 0x6071 is not available.

nDataOut5

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Mapping with:

  • SoE: S-0-0485 High velocity limit value
  • CoE: 0x60C9 High velocity limit value

nDataOut6

UDINT / DINT (4 byte)

or

UINT / INT (2 byte)

Mapping with:

  • SoE: S-0-0484 Low velocity limit value
  • CoE: 0x60C8 Low velocity limit value

nCtrl5

USINT

Mapping with:

  • CoE: 0x6060 Mode of operation

nCtrl6

USINT

reserved

nCtrl7

USINT

reserved

nCtrl8

USINT

reserved