Electric Motor Wiring help needed

[JP]

Hi folks,

I've got a Sanding center from a buddy (minus the drive motor) and a 115V 1/4hp electric motor from an old Maytag dryer.

The motor has 3 wires coming out. Red, White & Yellow. The White wire goes to one connector and then a blue wire hops from that connector to a different connector (not red or yellow)

How do I wire that to a standard polarized grounded plug?

[Dragonrider]

Hey JP,

I can probably help, but are you sure it is a 115V motor? If it is, I would suspect that the white is neutral, you would ground to the case, and the red and yellow are both hots, hook one up and the motor goes one way, hook the other up and the motor reverses. (only one of those at a time).

So, case to the ground on your plug (the roundish prong), white to the bigger blade, and red OR yellow to the other blade.

But that would be kind of an odd motor for a dryer . . .

It could also need a run or start capacitor . . . There is no data plate on the motor? You still got the dryer? Maybe a circuit diagram inside the cover somewhere . . .

If it is not 115V . . . then white is neutral, red and yellow are both hots on a 220V circuit.

Clamp it in a vise, stay clear and give it a try . . .

Those motors are pretty cheap if you want to buy a new one . . . check http://www.mcmaster.com/ . . . they will deliver to your door . . . you can also generally get them from you local air-conditioning shop.

[JP]

Originally posted by Dragonrider
Hey JP,

I can probably help, but are you sure it is a 115V motor? If it is, I would suspect that the white is neutral, you would ground to the case, and the red and yellow are both hots, hook one up and the motor goes one way, hook the other up and the motor reverses. (only one of those at a time).

So, case to the ground on your plug (the roundish prong), white to the bigger blade, and red OR yellow to the other blade.

But that would be kind of an odd motor for a dryer . . .

It might have been a washer. I don't know for sure. It says Maytag and it's definitely 115V. The Data plate was a paper sticker which is carmel colored now - probably discolored from the adhesive used to hold it in place. It's not easy to read it all.

BTW, there is also a spade connector on the motor with a green dot (Most likely ground?) which does not currently have a wire attached.

I had guessed what you're saying to be the case but it never hurts to ask one's betters for advice.

Thanks! Much obliged.

[Dragonrider]

Yah, washer makes more sense, they are 115v, and they do reverse the motor to operate the transmission.

Yah, the green spade/dot is the case ground . . . to the center/roundish plug on your standard polorized plug . . . the white to your larger blade, the red OR yellow to the other. Cap the unused wire . . .

Good luck, don't get zorked.

[JP]

Grrrrrrrrrr

With the white on white and green on green and red on black I can get it to turn clockwise but sadly I need it to turn counter clockwise.

Putting black on yellow does not make it turn the correct direction.

Any suggestions?

[Dragonrider]

I am assuming the black on yellow does nothing?

Then:

Some motors use the extra wire to "trigger" the direction . . . so, hook the red and yellow up to the black at the same time.

This is fairly common . . . but as we have no diagram here . . .

Stand back when you try it . . .

[JP]

Originally posted by Dragonrider
I am assuming the black on yellow does nothing?

correct.

Some motors use the extra wire to "trigger" the direction . . . so, hook the red and yellow up to the black at the same time.

This is fairly common . . . but as we have no diagram here . . .

Stand back when you try it . . .

Just tried that. Still clockwise

Think it might have something to do with that blue wire that piggybacks off white?

[Mike Hart]

You are hooking this motor up to a pulley drive? Can you rig it to run from the other side? (turn it around) ah, that's probably too easy, you already thought of that.

It's been a long time, but aren't ac motors made to run in one direction only? DC motors are reversible depending on polarity, but AC motors? No, that's single phase... dang, senior moment...

[JP]

The mounting plate is between the legs of the sanding station.

I suppose I could turn the motor around but that would would require a good bit of fabricating to make a mount for it and would probably cause me to whack my leg or knee on it as I used the disk sander.

BTW, it does say it's a 1 phase motor on the sticker. Does that mean it's all over?

[Dragonrider]

DC motors are easily reversable . . . switch the polarity.

Many many many AC motors (about 50%) are also reversable . . . but that requires additional wiring inside them . . . as they are normally "biased" to start in a certain direction. If they were not biased, it would be random what direction they started in . . . and may not start without a spin to get them going . . .

So they bias the winding.

To reverse an AC motor they can not bias the main windings, and add additional windings that can be hooked into the circuit to bias the motor to start in a certian direction . . . or in the smaller motors, they often have complete different windings (one for each direction).

[Dragonrider]

So, sounds like JP's motor is normally biased to run one way, and hooking the yellow into the circuit will bias it to run the other way. Washing machine motors are almost always reversable . . . they are belt connected to a transmission that spins the tub when turned one way, and occilates the tub when turned the other way.

So, my recomendation is,

green to ground.
red and yellow together to black.
white to white.

[Mike Hart]

I looked around a bit to refresh my memory, but only confused myself further Starting with Tesla, the AC motor field is vast. Your motor may be reversible, or not. Just offhand, I'd say 3 wires (only 3 wires) is a clue that it is probably not.

Hey, what if there was a forum, like xs11.com, where people talked about washing machines?

http://pub103.ezboard.com/fappliancerepairdryers

[JP]

I still think it came off a dryer. A gas dryer. I don't have 220 in the laundryroom. I remember pulling off the motors of both the washer and dryer but I think the washer motor was really strange looking.

I did combine the red and yellow together to black, green to ground & white to white. Still only goes clockwise. I don't know why there would be a red AND yellow wire but there is.

I just wish it went counter clockwise.

[JP]

Maybe yellow on black is a different speed? I'll try it tomorrow and see. Might have to get a different motor if I want one to go counter-clockwise.

[JP]

Nope, didn't change a thing.

The Yellow wire added to the circuit (or disconnected completely) alters nothing. Maybe whatever it's supposed to do is fried.

No matter. I'll find something to do with that motor. Maybe make a polishing stand with a pillow block. Someday.