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Entry type: FAQ Entry ID: 90161753, Entry date: 04/09/2014

SINUMERIK 810D/840D: Reading out the drive data via the NCVAR selector

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What is important when reading out drive data via the NCVAR selector?

See the following table for the requirements for reading out drive data.

Enabl Option
General NC enable Evaluation of internal drive variables
(order number 6FC5251-0AB17-0AA0)
Axis-specific enable Detection of additional drive actual values

With MD36730 $MA_DRIVE_SIGNAL_TRACKING = 1, acquisition of the following drive actual values is activated (if they are provided by the drive):

  • $AA_LOAD drive load
  • $AA_POWER drive active power
  • $AA_TORQUE drive torque setpoint
  • $AA_CURR smoothed current actual value (quadrature-axis current) of the drive

During operation of the NC control, different conditions arise. Similarly, system-specific data can change during operation. These data are termed status data as opposed to system data. A distinction is made between

  • NCK-specific status data
  • Mode-group-specific status data
  • Channel-specific status data
  • Drive-specific status data (FDD)
  • Drive-specific status data (MSD)

You will find drive-specific status data feed drive (FDD) in area V, block S of the NCVAR selector.

No cyclic service must be set up on variables in this block. Only individual variable accesses are permitted.

You will find drive-specific status data main spindle drive (MSD) in area H, block S of the NCVAR selector.

Addressing of the H-S block is not possible in MMC100/EBF/OP 030.

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