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Posted By: Joetools 4pdt switch for reversing motor - 02/05/11 09:51 PM
does anyone know where i can find a schematic for wiring a single phase, 120v rvsing motor using a 4pole, dbl throw toggle?
Posted By: gfretwell Re: 4pdt switch for reversing motor - 02/06/11 12:48 AM
Basically you just swap the orange and black wire on most of the motors I see.

Use the standard cross connect method on the DPDT sw.

[Linked Image from gfretwell.com]

Furnas has a lot of diagrams for doing this with their drum switches and various motors.
See page 5
http://gfretwell.com/electrical/Catalog%204258%20Drum%20Controllers.pdf

Posted By: Tesla Re: 4pdt switch for reversing motor - 02/06/11 02:16 AM
I've even worked with three-position double-throw switches -- as toggles.

Forward - off - reverse.

Is this a gear-motor?
Posted By: gfretwell Re: 4pdt switch for reversing motor - 02/06/11 03:31 AM
That is what the drum switches are good for. We have thousands of them here on boat lifts. They use the garden variety 6 lead induction motor in the top left of figure 1 of the Furnas diagrams I referenced. Those are dual voltage, reversible.
Posted By: Joetools Re: 4pdt switch for reversing motor - 02/06/11 05:12 AM
yes, it's a 3pos switch, fwd/off/rvs 4 pole (12 terminal) dbl throw switch. 6 leads coming from motor. boss wants me to use this switch. haven't had much luck looking for a schematic online..?
Posted By: gfretwell Re: 4pdt switch for reversing motor - 02/06/11 06:19 AM
Does this help?

This is how the drum switch does it.

[Linked Image from gfretwell.com]

I have never seen it done with 4pDT but if you see the connections necessary we should be able to figure it out.
Posted By: gfretwell Re: 4pdt switch for reversing motor - 02/06/11 06:51 AM
Try this.

Someone check my logic, it is late wink

120v wired 6 wire motor

[Linked Image from gfretwell.com]
Posted By: Tesla Re: 4pdt switch for reversing motor - 02/06/11 08:22 PM
My style is to bring L1,L2 to the center, common connections. In the center off position the voltage goes no further.

Then Fwd/Reverse use mirrored connections... with either the Run or Start leads flopped.

But that's not the only way to skin a rabbit.

BTW, with my scheme you don't need so many poles.
Posted By: gfretwell Re: 4pdt switch for reversing motor - 02/06/11 11:16 PM
I was just going for no power ti the motor when it was "off". I see where you could do a couple of different solutions to this puzzle.

The real answer is a drum switch IMHO. They are definitely motor rated and pretty robust. Like I said up thread, we have thousands of them down here on boat lifts. That is why I knew about the black and orange wire thing ;-)
Posted By: gfretwell Re: 4pdt switch for reversing motor - 02/07/11 01:25 AM
I agree Tesla
I redrew the picture to make it easier to see.
You could eliminate the top set of contacts as long as this is a Line/Neutral motor. (wired 120v)
Posted By: Joetools Re: 4pdt switch for reversing motor - 02/09/11 01:58 AM
thanks, i'll try this out.

is a contactor necessary here? the switch is rated 120v. it's a 1/2hp motor.
Posted By: gfretwell Re: 4pdt switch for reversing motor - 02/09/11 07:46 PM
You need a "motor rated" switch. If your switch is OK for a 15 or 20a inductive load it should work but a lot of these say "resistive load only" or words to that effect. That is why I said a drum switch like the Furnas is a good choice. They will work for years without any problems. You can also get them in 3R enclosures if this is outside.
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