120V 3-phase washing machine motor help?

[Homercidal]

A friend of my sister's has a broken washer and I volunteered to have a look since a) I'm a nice guy, and b) washing machines are generally dead simple devices.

Well, the thing doesn't agitate or spin. The motor doesn't turn at all. The drain pump works fine, as does the fill valves, etc. I've metered the leads on the motor and it's getting 120V on several of them.

The thing is, it's a 120V 60-cycle 3-phase motor! I guess they use these now because they can vary the speeds and they are fairly high torque, and hence use a simpler transmission.

Anyway, I don't know which leads do what, and even if this thing should spin if it's got 120V going to some of the leads. Might it require some other input to get it started?

It's got a circuit board on top of the motor, under a cover. This is the 3-phase inverter/speed control circuit and it looks fine (Although this does not mean it's not damaged.)

I just don't know enough about these things to know if it will spin unless some other wires tell the circuit board to power the windings. I'd like to be able to get their washer fixed for them, but I'm down to this and honestly this thing is inexpensive enough that they could replace it with a similar used one for $50-100.

I didn't think to look for a schematic inside the door panel when I had it off the machine.

 

[PartagasD4]

http://www.waterfront-woods.com/Articles/phaseconverter.htm

This website is for woodworking tools like lathes but should explain the basic
principle behind 3 phase motors used in single phase homes. It is really not to hard to understand as long as you have prior experience with some electrical.
If the motor is shot it is usually not worth replacing unless you can get a good price on a used working one. Most likely it comes as an assembly and can be more than an older washer is worth.
hope it helps

 

[Homercidal]

http://www.waterfront-woods.com/Articles/phaseconverter.htm

This website is for woodworking tools like lathes but should explain the basic
principle behind 3 phase motors used in single phase homes. It is really not to hard to understand as long as you have prior experience with some electrical.
If the motor is shot it is usually not worth replacing unless you can get a good price on a used working one. Most likely it comes as an assembly and can be more than an older washer is worth.
hope it helps

That's great, but it doesn't help me know how the circuit they built for the washing machine is put together. I am sure the washer timer tells the circuit what speed to turn and which direction. I just don't know if the motor requires that information in order to turn, and if so, how do I emulate that to check if the motor or circuit is damaged?

Even the guys in a nearby logic control business seemed surprised to find a 120V 3-phase motor on Single Phase wiring, and had nothing to contribute for troubleshooting without a schematic.

Can't find one online.

 

[Homercidal]

I actually found some Youtube videos on these things! Apparently it's got a small LED light for troubleshooting. I got to put it back in the machine and give it a test.

 

[BeerMakesPeopleHappy]

More often than not it's the motor controller that's failed. Although I've been out of the appliance repair business for quite a while, so things may have changed a lot since then.