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AC Motor Wiring ?

AC Motor Wiring ?

RE: AC Motor Wiring ?

It looks like a 2-speed motor, with connection to either white & black for high speed, or white & yellow for low speed.

There should be a 20uF capacitor with the motor, typically a plastic or aluminium can about 1.5" diameter and maybe 4" long. That's 'C' on the diagram, connect it to the red and orange leads.

There's a thermal overload which looks like it is a self-resetting Klixon type. Your should be able to verify continuity between the white and red leads to prove it is OK.

RE: AC Motor Wiring ?

Thank you, Scotty. Would the motor work if the capacitor were omitted and the orange and red leads were simply connected? Or is the cap needed as a "start-up capacitor"?

Thanks again.

RE: AC Motor Wiring ?

You need the Cap.
It should be rated for continuous duty, not a starting capacitor.

"Why not the best?"
Jimmy Carter

RE: AC Motor Wiring ?

Bill, Thanks for the information.
After some research, I believe the capacitor causes a 90-degree phase shift which determines the rotation direction of the motor. Moving the capacitor to the other winding should reverse the rotation direction. Is my understanding correct?

RE: AC Motor Wiring ?

With the connections available to you I don't think you can reverse this one electrically, although I could be wrong. You would need to reverse the polarity of either the start winding or the main winding, and the winding ends aren't brought out - there's an inaccessible connection brought out on a single black wire.

A trick I've used on very small shaded pole motors - which are inherently non-reversible - is to dismantle the motor and physically reverse the rotor so that the shaft is at the other end, assuming the bearings and end-bells allow you to do this. You may have the option here, and I think it should be simple enough on this motor because it looks like a permanent split capacitor motor rather than a cap start, induction run type. The latter can be fiddly because of an internal shaft-mounted switch which disconnects the start winding once the motor is at running speed, but I don't think that's what you have here.

RE: AC Motor Wiring ?

In most permanent split capacitor motors one winding is designed to run in series with a capacitor and the other winding is designed to be connected directly across the line.
There is one exception. There is a type of small motor with two identical windings that is reversed by switching the capacitor from one winding to the other. Your motor is not such a type.
I agree with Scotty's suggestion.

"Why not the best?"
Jimmy Carter

RE: AC Motor Wiring ?

Thank you, Scotty and Bill, for the information.

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