KEB COMBIVERT F5 Operation Manual page 126

Learn Procedure Troubleshooting
Problem:
Unable to complete Encoder Pole
Position Learn successfully
126
Troubleshoot:
Ensure brake picks and the sheave is free to move relatively easily;
should be able to rotate by hand.
If the displayed position does not appear to change and the
sheave does not move back and forth by a few inches, then the
sheave is unable to move freely and the procedure cannot be
complete.
Ensure correct motor U, V, W phasing.