PM935TS 3 phase whine

[websocket]

My mill has a whining noise. The slower the speed, the higher it is. It seems to be the motor and not the pulleys. I remember watching a Cough42 video where he had a similar sound and changed a VFD setting that fixed it. Is this something I can address in my Hitachi VFD?

 

[machPete99]

I think the setting is called "carrier frequency" or similar (B083 setting on mine). If you bump it to the highest levels the noise is still there but (mostly) inaudible to humans. (Your dog may still get annoyed though).

 

[websocket]

Much better. Thank you!

 

[markba633csi]

Check the motor case temperature after running for a while at the higher frequency- If I recall the temp might increase
a bit with the higher setting- the VFD will also heat a bit more

 

[rabler]

Yeah, the right answer is to bump that VFD frequency up until the whine just goes away from your hearing, not to the maximum frequency, as high frequency has downsides to the motor and the VFD. Your VFD may have a threshold frequency charted/listed in the manual above which you need to derate the VFD. But changing the frequency is pretty much routine with VFD's, surprised PM didn't ship that way.

Typically your wife (assuming you're married) will hear the whine at a somewhat higher frequncy than you. I'll leave that to you to decide if/how that matters

 

[markba633csi]

Girlfriends also have that valuable/annoying trait, I've found.