best practice

EtherCAT rate (EC_RATE)

The default EtherCAT frame rate in ecmc is set to 1kHz. For most applications this is however not needed and can therefore be reduced. A reduced EtherCAT rate reduces the load on the controller. In general, a good value for the frame rate is in the range 100Hz to 1kHz. For motion systems, a frame rate of 100Hz..500Hz is normally enough. Rates outside the 100Hz..1kHz range is normally not a good idea, and some slaves might not support it. However, in special cases both lower and higher rates might be possible and required.

Example: Set rate to 500Hz

require ecmccfg "EC_RATE=500"
...

For more information see the chapter startup.cmd.

As a comparison, TwinCAT default EtherCAT rates are:

  • 100Hz for PLC
  • 500Hz for motion

See host/ecmc_server for more information.

ecmc server setup

  • If possible, make sure the native igb ethercat driver is used.

For more information see: