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FW version: Stable

What does the error code "phase CM" mean?

If you see an error code with the following text:

  • phase X CM
  • phase X/Y CM diff

where X, Y is the phase name (A,B,C)

These error codes indicate a problem with the controller's current measurement circuit. Testing of these error codes is during the controller's initialization.

What can cause the error?​

  1. Leakage current in the motor phases - The leakage current is usually caused by humidity or mechanical damage in the motor windings. Make sure that all the phase cables and motor windings are in normal conditions
  2. Damaged controller - The current measurement circuit is a delicate piece of HW. It is crucial for proper controller operation and the error thresholds for the error detection are very tight. It can happen that a HW problem will occur.

How to check what caused the error?​

  • Disconnect the motor phases and turn on the controller .
  • If the error code is gone, inspect the motor and the phase cables. If one of these error codes is preserved, the problem is probably with the controller, and contact our support.