VFD whine on Oliver 2159 wood lathe -how to fix?

Hello everyone,

I recently installed a KB electronics (model KBAC-24D) VFD on my Oliver 2159 wood lathe. I bypassed the starter and a microswitch in the headstock of the lathe, and I am 99% sure I installed the VFD correctly. I bought this particular VFD because it does not need to be programmed and the adjustments are analogue.

Everything works as it should.
The only only issue I have is that the lathe motor makes a high pitched whine, that is very annoying, that I still hear with ear protection.

I contacted KB electronics and a tech at the company where I bought the drive and they mentioned adjusting the slip compensation and the boost trim pots in the VFD.
I did that and it seems like it made some improvement, but the whine is definitely still there.
The carrier frequency adjustment is factory set to 16 kilohertz on the VFD, so I can't adjust that.

The tech I spoke with told me a newer motor would work better with the drive... mentioning a Marathon micromax 1 hp inverter duty motor.

(I suppose I could also install a single phase motor on this lathe, however this lathe has a reeves drive that only goes down to 1000 rpm's and without the VFD I would loose the ability to slow the lathe down for bowl turning)

If I replaced the old motor with this new motor do you think it would solve the noise problem?
It seems a little overkill, partly because this is not an easy motor to replace...
but I plan on using this lathe a lot in my lifetime, and I know the noise will drive me crazy.


Any thoughts would be appreciated. Thanks, Andrew

Many VFDs use a version of pulse width modulation to adjust the output frequency. The problem with that technology is that it creates a lot of harmonics. What you're hearing is vibration of parts of the motor to one or more of the harmonics. There are VFDs that do a better job of outputting a cleaner sine wave and they would likely solve the problem. A different motor might solve the problem or it might not.

Mike

[I'd probably return the VFD - if you can - and when you go to purchase a new one, discuss the problem of the noise with the seller and see if they can offer a reasonable alternative.]

You might look into adding a filter between the VFD and motor.

It's common for VFD-driven motors to make audible noise, especially when driven well below rated speed. It may be unavoidable.

Have you installed a sealed cabinet for the VFD ?
What about shielded/armored SY cable between the motor and the VFD?
How far is the VFD from the motor?

Tom

You might want to install a load reactor between the motor and VFD. I suppose a line reactor could help as well. I think the carrier frequency needs to be tuned for your motor. Shielded supply cable to motor will help as suggestec previously.
The first thing is to shift the carrier frequency. The maker may say it is fixed but they know how to set it at the factory.

Hello Andrew -

Did you come to a satisfactory solution with this problem? I also have an Oliver 2159 and considering the same KC VFD. How is it working for you now after a couple of years?

Thanks!

Michael

I also have an Oliver 1259 that I restored. I am running a Teco MA7200 VFD purchased from Factorymation. I am also using the same VFD on my Oliver 167. I have had no issues with either.

Another thing to remember with the Oliver 159’s and 2159’s, is that Oliver used an odd motor mount, and fitting a different motor can be a challenge.

Thanks Bruce - I'll check out the Teco. What was involved in your restoration?

Michael

Michael,

the restoration was was from the primer up. There is really not all that much to restore. Put new bearings in the headstock and the motor. Clean up the Reeves drive, replace the drive belt, and you are good to go. Your lathe probably has some combination of a magnetic starter and/or a start/stop station or a micro switch. The micro switch is activated by the speed control handle. All of these should be bypassed, as you do not want a disconnect between the motor and the VFD.

You will really like the combination of the Reeves drive and electronic speed control. This combination gives infinite speeds with no loss of torque. You will probably find that the variable speed pulleys are steel and brass. There is not pot metal on your lathe.

You can get a manual and parts list from Eagle Machinery. http://www.eaglemachinery-repair.com/

Bruce