James42005
Member
Question/Issue: I have PF753 running a 150hp motor (piston pump). For years the techs/operators have had an issue starting this motor. It appeared as if it was single phasing. The rotor would turn a few degrees then slam back the opposite direction, back and forth and not actually start. The simple solution for the longest time was to simply rotate the motor by hand about 90 degrees and then it would restart just fine. Not long ago the drive was replaced for a different issue, but also hoped it would cure the starting issue we would see sporadically. It did not. Recently we could not get the motor started even after a manual spin of the rotor. Decision was made the swap motors even though electrically everything tested fine. New motor did exact same thing, unfortunately. So long story short and a few dollars later it appears to be a setup/programming issue in the VFD all along. We have made a few changes and are able to start the motor, but there is still a short period of what looks like single phasing before the motor finally spins up. Any suggestions on parameters to take a look at to achieve a smooth start? FYI the motor only starts a few times per week, and runs pretty much continuously. Also, never faults VFD.
Thanks
Thanks