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Scoping the Resolver or Sine Encoder Signal Amplitude in AKD

First to review what F402 means:

Analog signal amplitude for resolver or sine encoder feedback is out of range, either too low or too high.

To troubleshoot:

Check primary feedback (X10 connection), for resolver and sine/cos encoder only.

Use the Workbench scope to record the signal amplitude (sum of squares) and see if the signal amplitude is out of range.  The problem is typically a bad encoder, EMI, or a bad wiring connection.  If the encoder or resolver rotor has been displaced axially, that can cause the amplitude to be out of range.  EMI will typically cause spikes.  Seeing in the scope where the spikes occur can give some direction for troubleshooting.  If the spike (and F402 fault) always occurs immediately when the drive is enabled, then it is probably EMI from the motor power PWM coming from the motor power cable.

See downloadable PDF for procedures.