replying to Wild Bill, Confused wrote:
Hi I have a bench grinder that I converted for polishing. Recently the thing
has lost power when I push against the polishing mop and I can even stop it
rotating if I grab hold, can anyone loll me whats up. Ive opened it up
and had a look, no debris or broken parts, no bearing wobble. Is it the
capacitor or is it toast?

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On 2019-04-28, Confused wrote:
replying to Wild Bill, Confused wrote:
Hi I have a bench grinder that I converted for polishing. Recently the thing
has lost power when I push against the polishing mop and I can even stop it
rotating if I grab hold, can anyone loll me whats up. Ive opened it up
and had a look, no debris or broken parts, no bearing wobble. Is it the
capacitor or is it toast?

Almost certainly the capacitor. And they are cheap, so get a
replacement and swap it in.

You probably cooked the capacitor when pushing too hard against
the mop and stalling it, which results in the start centrifugal switch
closing, and applying power to the capacitor for too long. They can
only take a very short application of the AC which drives the motor.

Get several spare caps, as you will probably be killing more of
them in this application.

Better if you have a three-phase motor and a VFD to drive it.
That can take the extra load a lot better than a cap-start motor.

Good Luck,
DoN.

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On Sun, 28 Apr 2019 19:18:02 GMT, Confused
wrote:

replying to Wild Bill, Confused wrote:
Hi I have a bench grinder that I converted for polishing. Recently the thing
has lost power when I push against the polishing mop and I can even stop it
rotating if I grab hold, can anyone loll me whats up. Ive opened it up
and had a look, no debris or broken parts, no bearing wobble. Is it the
capacitor or is it toast?

It could..could be the capacitor..which typically is only used for
starting if there is a single cap. Clean up the contacts and check the
movement of your centrifugal starting switch..which it may..may have.

If both are ok..you have a bad winding.

__

"Poor widdle Wudy...mentally ill, lies constantly, doesnt know who he is, or even what gender "he" is.

No more pathetic creature has ever walked the earth. But...he is locked into a mental hospital for the safety of the public.

Which is a very good thing."

Asun rauhassa, valmistaudun sotaan.


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