[EtherCAT / MyActuator] Motor Reaches Operation Enabled but Produces No Torque

[EtherCAT / MyActuator] Motor Reaches Operation Enabled but Produces No Torque

Problem

A MyActuator RMD motor transitions to Operation Enabled, but:

  • Produces no torque
  • Does not move
  • Returns zero feedback values
  • Shows no faults or alarms

Environment

  • OS: Windows 11
  • Device: MyActuator RMD motor
  • Communication: EtherCAT (RapidSetup)
  • State: CiA 402 reaches Operation Enabled

Symptoms

  • Motor is completely silent (no holding torque)
  • No movement
  • Feedback values are all zero (position, velocity, torque)
  • Mode of Operation Display (0x6061) = 0
  • No drive faults

Root Cause

Distributed Clock (DC) Synchronization is not enabled.

  • EtherCAT communication is working
  • CiA 402 state machine completes
  • Internal motor control loop does not start without DC Sync

SM-Synchron allows communication but does not provide timing for control loop.


Solution

1. Modify ESI File

Edit the section to force DC-Synchron only and remove SM-Synchron entries.

2. Clear Cached Files

Delete:

  • ESICache
  • EtherCAT folder
  • .bin folder

3. Regenerate ENI

Rebuild configuration in RapidSetup.


Notes / Gotchas

CustomNodeInfo.xml

  • Ensure ModeOfOperation is defined

PDO Naming

  • Inputs: SND PDO Mapping0.
  • Outputs: RCV PDO Mapping0.

Key Insight

“Operation Enabled” does not guarantee motion.


Takeaway

This is a synchronization issue, not a communication issue.