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I'm getting an F401 Error on the AKD Servo Drive

The F401 error results when parameters related to the anticipated feedback device are in error.  There are a number of reasons this could be seen, and typically, it is related to a non plug-and-play device is in use, and the AKD is expecting one. This short video clip explains how the drive can be properly set up for a non plug-and-play device.

There may be other reasons for this error as well - as an example, we are connecting an AKM32D-ACCNR-00 to the AKD servo drive.  This is utilizing a resolver for feedback.  It is possible there could also be an issue with the cables, or the resolver itself.  To further troubleshoot this issue, we will look at the following:

  1. Confirm (in this case) the correct feedback cable is being used.  For the example motor above, the correct feedback cable is the VF-RA2474N-xx (the xx indicates length in meters).
  2. Was the F401 the only fault received?  Was fault F532 also present?  Likely due to incorrect setup in workbench (See video above)
  3. Was the fault F402 present as well?  F402 is related to the analog signal amplitude being received from the feedback device.  If this is too low, this may point to wiring issues, or potentially a defective feedback device.

If the cable is correct, the wiring is confirmed, and you are seeing F401 and F402, the resolver may be the culprit.  Using the procedure in the document below, you can determine if the amplitude is to low.  Following this procedure, the amplitude of the resolver should be between 6,124 and 11,788 counts.  The graph below shows an average signal value of below 3,716 counts, pointing to a suspect resolver.


For more information about the F402 fault, see the following article and procedure: Scoping the Resolver or Sine Encoder Signal Amplitude in AKD