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Posted By: rj Reversing motor with a switch - 09/20/05 11:37 PM
Ok guys I am having a VERY BIG brain fart. I'm having a hard time remembering what happens to all the contections when using a toggle switch to reverse the rotation of the motor. Like the black wire is hot and the red wire at the motor is one direction and the yellow is another direction. I have not worked around this application that much and need some help on rembering. SORRY FOR ASKING BUT I AM HAVING A REALLY BAD DAY!!!!!!!
Thanks to all who can help
Posted By: winnie Re: Reversing motor with a switch - 09/21/05 01:29 AM
Dare I say that the answer will be different for different types of motor, and that the only way to correctly do this is to start with the motor connection diagram.

There are some easy ones, eg. a three phase motor is reversed by swapping any two leads, and some single phase motors are reversed by swapping connections on the start winding. Some motors cannot be reversed by a simple lead change.

The motor connection diagram is often found on the nameplate or in the terminal box.

-Jon
Posted By: livetoride Re: Reversing motor with a switch - 09/21/05 01:46 AM
As winnie said it depends on the motor. Swapping red and yellow sounds like a 110v a double pole double throw switch may be what you need. Yellow on one pole and red on the other. Just a guess. Rod
Posted By: gfretwell Re: Reversing motor with a switch - 09/21/05 02:35 AM
http://www.hubbell-icd.com/icd/drum/files/Catalog%204258%20Drum%20Controllers.pdf


This has a lot of connection diagrams down on the last few pages and it has rescued me a few times working with less than direct replacement motors.
Posted By: classicsat Re: Reversing motor with a switch - 09/22/05 12:52 AM
Assuming a single phase resistance start:

It depends on the motor, but generally, you swap the aux(start) winding leads. The ones I am familiar with are marked T5 and T8. The ones with the coloured wires are Red and Black. That is my experience, your motor could be different.

There could be creative ways with a toggle switch, but all I have ever used is those rotary reversing levers.
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