So I need to try a couple more things to know where the problem lies.

Thanks people,
Steve

Bob Engelhardt wrote:

R. O'Brian wrote:

The motor is the problem. ...


I'm certainly no expert, but I have a little direct experience with
this. I have a 3 ph motor and VFD on my drill press. It is the 2nd
VFD. The first one sang, this one does not. Same motor, same wiring.

Bob