# VFD motor whine



## cpd62 (Sep 26, 2013)

OK, so I got my VFD running on the drill press (3/4 hp 60 hz 3 phase Baldor motor hooked to a ABB VFD).

Thanks to everyone here for advise.  Pretty simple to setup actually.

The motor whines at the lower speeds.  It's nice and quiet at the upper end.  I set the nominal frequency to the motor frequency at 60 Hz.  I have been adjusting max frequency to see if it goes away.  The lower end (lower 1/3-1/2) of the pot. speed scale generates a whine in the motor.

Any suggestions on how to minimize this?

Thanks,
Christian


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## DAN_IN_MN (Sep 26, 2013)

Toss it a block of cheese! :rofl:

Sorry, that was the only help I could think of! :jester:


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## itsme_Bernie (Sep 26, 2013)

cpd62 said:


> OK, so I got my VFD running on the drill press (3/4 hp 60 hz 3 phase Baldor motor hooked to a ABB VFD).
> 
> Thanks to everyone here for advise.  Pretty simple to setup actually.
> 
> ...



I have VFD set upon a few machines. I share it with twist lock connectors when I go from one to the other.

There is a "carrier" frequency that can be changed, and audibly changes as well.  This helped me a lot. Some of it could be the motor.  

What kind do VFD are you running? 


Bernie


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## DAN_IN_MN (Sep 26, 2013)

itsme_Bernie said:


> I have VFD set upon a few machines. I share it with twist lock connectors when I go from one to the other.
> 
> There is a "carrier" frequency that can be changed, and audibly changes as well.  This helped me a lot. Some of it could be the motor.
> 
> ...



The stepper motors on the CNC plasma cutter I run give off a pitch that changes with RPM.


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## cpd62 (Sep 26, 2013)

DAN_IN_MN said:


> The stepper motors on the CNC plasma cutter I run give off a pitch that changes with RPM.



It's an ABB ACS150 VFD.  The whine is gone when I'm running at 50hz or higher, not bad 40-50Hz and pretty noticeable below 30Hz.

It's pretty slick for the most part.  The motor is brand new and at 60Hz sounds super smooth.  The whine comes in at pretty slow speeds so even if I'm stuck with it probably no big deal.  Just wondering if I could tweak it to eliminate or dampen more.

Christian


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## itsme_Bernie (Sep 26, 2013)

There will be some whine, but it can be adjusted quite a bit with the settings.

It is usually better at full speed and louder at low, but this can be improved.   


Bernie


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## CluelessNewB (Sep 26, 2013)

I have never used an ABB VFD but from the online manual it looks like you can adjust the carrier frequency (switching frequency) see parameters 2606, 2607 and 2609 on pages 105 and 106.  It looks like the default is 4 KHz but you can go up to 16 kHz.  The higher you set it the less noise but there is a tradeoff because it will run hotter. Also see page 139 for additional info. Below is a link to the manual I found online.     




http://www05.abb.com/global/scot/scot201.nsf/veritydisplay/fb7940e93ef40d8dc12578220038ffa9/$file/EN_ACS150%20UM_rev%20C_A4_screen.pdf


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## cpd62 (Sep 27, 2013)

CluelessNewB said:


> I have never used an ABB VFD but from the online manual it looks like you can adjust the carrier frequency (switching frequency) see parameters 2606, 2607 and 2609 on pages 105 and 106.  It looks like the default is 4 KHz but you can go up to 16 kHz.  The higher you set it the less noise but there is a tradeoff because it will run hotter. Also see page 139 for additional info. Below is a link to the manual I found online.
> 
> 
> 
> ...



I found this but have had trouble with these 2 parameters. All other programming has been rather obvious and user friendly. I have left a message with tech support.


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## Ray C (Sep 27, 2013)

Just an FYI here...  Running at low speeds with a VFD can heat-up the motor a good bit and also, at lower RPMs, you're not getting much horsepower.  My practice is to set the VFD to only allow variation between 50 and 60 Hz.  Some folks have adopted similar guidelines of around 45 to 65...  For sure though, once you get into the 40 range, the motor is significantly derated horsepower -and in some cases with older motors, it's not spinning fast enough to effectively cool itself.


Ray


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## rdhem2 (Sep 27, 2013)

Ray nailed it pretty well.  When I set up drives for people I purposely set minimum speed no lower than 20-25Hz.  Mainly for cooling the motor reasons.  Few people ever invest in a INVERTER RATED MOTOR.  

If you can't get the speed low enough with the pot, mechanically change the speed like you used to do then operate 20-60Hz within that range but keep the hertzs at the upper end of the scale.  By doing this you truly have infinite fine speed control.

The whine goes away after a couple minutes of work.  You just don't hear it anymore!


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## cpd62 (Sep 27, 2013)

I talked to tech support today.  For the ABB 150 ACS to switch carrier frequency you go to Long parameter mode then switch to mode 26 then 2606


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