How to wire a 220 volt compressor motor...

[Brutpwr]

Have a big 220 volt compressor I have not used in a bit since the last shop I was in did not have adaquate power/panel in my section of the shared/divided building. There are four black wires that come out of the motor. As I recall two pairs of each go to each leg of power. I tried hooking up the two pairs that seemed to next to each other an flipped the breaker and nothing happened. I remember have this problem when I had to buy a new motor and if you got the wrong pairs hooked up the breaker would trip if you got it wrong and the motor would spin if you got it right. It has been stored outside for a bit so may be the contacts got rusted? but I can't believe they are made of metal so wtf? It seems to have power all the way to the motor so I'm guessing all the contact switches are passing power. Anyway to ohm out the leads to be sure the motor is not fried. I did loan the compressor to a friend as I could not use it but it does not smell burnt up or anything.

Thanks,
Jason :)

[D60]

You're sure this is a single phase motor?

[bgaidan]

What kind of motor?

Can you take the back plate off and see where the wires go. If you can trace them it should be obvious what needs to be paired.

[Josh83]

Ohm all of the leads to ground. Non of them should ring to ground. Ohm all of the leads to eachother. Lets say they are labled ABCD. If the motor leads are as you say do it like this. Ring A to the other three. It should only ring to one. Say it rings to C. Those two are a pair and then the other two (B and D) should ring to eachother, but not to the other two(ie: neither A nor C should ring to B or D). I understand the wires are probobly not actually labled, I'm just typing it out that way to make it a little more understadable. Clear as mud?:D

[azhayseed]

Sounds to me like you have a dual voltage motor 120/240 volts.
If this is the case you have 2 sets of windings they will be hooked up in parallel for one voltage and series for the other voltage.
There should be some sort of wiring information on the motor some where, usually inside the cover that goes over the wire connection or on the motor ID plate. As Josh said above, the leads would be ABCD or 1234, A-B would be one set of windings , C-D would be the other set of windings.
Series: Power to A, other leg of power to D with B&C tied together would probably be for 240 Volts.
Parallel: A&C tie together with one leg of power, and B&D tied together with common would be for 120 Volts.
Disclaimer: I may have the voltages mixed up as to which one is for series and parallel...hey I'm getting to be an old geezer and sometimers desease is kicking in!
Also this may not be the only reason you have four leads, these may also be used to reverse the motor rotation some how. Use this info at your own risk.
The best way to deal with this would be take the motor to a motor rewind shop and ask them how it needs to be hooked up.

[Brutpwr]

Thanks for the help so far. Yes this is single phase. I don't think this is a dual voltage motor as this draws like 20 or 30 amps on 220! It requires a 60 amp breaker to start up from any pressures above 140 psi! I will ohm out the leads--that makes sence since the windings have to be connected. Might show if the brushes on one side are bad etc. If the motor has one set of winding that are bad would the motor hum or try to turn??? with power applied. Well I'll ohm it out tommorow.

Jason :)