Motor not running

[JdoubleU]

Ok, here is the issue. A 208v single phase cooling tower pump motor for a freezer is not working. I ohmed between the 2 conductors going to the motor and Got 6.5ohm. Is this normal. I ohmed them to ground and nothing is going to ground. The fLA of this motor I think was aroung 5 amps. I also spun the motor and it turned fine. I then tested the capacitor and it is good. Does anyone have an Idea what is wronge with it?

 

[mcclary's electrical]

Ok, here is the issue. A 208v single phase cooling tower pump motor for a freezer is not working. I ohmed between the 2 conductors going to the motor and Got 6.5ohm. Is this normal. I ohmed them to ground and nothing is going to ground. The fLA of this motor I think was aroung 5 amps. I also spun the motor and it turned fine. I then tested the capacitor and it is good. Does anyone have an Idea what is wronge with it?

Did you have the conductors de-termed from the motor when you did this? Have you megged the wire? Have you megged the motor? What did you test the cap with? HAve you guaranteed there is voltage at the motor?

 

[iwire]

If you know you have the correct voltage arriving at the motor leads and the motor does not turn and is small enough to have a capacitor then throw it out and order a new one because it is junk.

Graingers is a good source for small motors if you have an account.

 

[Cold Fusion]

From Jakewhis;1196122
Ok, here is the issue. A 208v single phase cooling tower pump motor for a freezer is not working. I ohmed between the 2 conductors going to the motor and Got 6.5ohm. Is this normal.
I wouldn't know if that was normal or not. Do you have another motor you can check? Were you at the motor terminals or at the starter - ie did your measurement include the conductor resistance? - cf

I ohmed them to ground and nothing is going to ground.
That's good - cf

The fLA of this motor I think was aroung 5 amps.
Guessing isn't usually good. You may wish to check the nameplate or the manual. - cf

I also spun the motor and it turned fine. I then tested the capacitor and it is good.
That's good - cf

Does anyone have an Idea what is wronge with it
I'd probably check to see if it actually had power at the conductor leads going out to the motor when it was susposed to be running - cf

 

[JdoubleU]

Did you have the conductors de-termed from the motor when you did this? Have you megged the wire? Have you megged the motor? What did you test the cap with? HAve you guaranteed there is voltage at the motor?

If the insulation on motor windings were bad would the motor lock up because that is what it is doing.

 

[hurk27]

If the insulation on motor windings were bad would the motor lock up because that is what it is doing.

No if the insulation on the windings was bad it would short out and open the overload or protective device on the circuit.

If you are saying when you apply power it acts like it is locked up and just sits there and hums, then you have a bad centrifugal switch in the back bell housing or the start windings/ cap is bad.

Try this:

Unhook the motor from the load it drives, spin the rotor as fast as you can, stand back and apply power and see if it will take off, if it does it has a bad CS as stated above or a bad start winding, or a bad start cap.

This does not work for all S/P motors as some use the start windings as part of the run windings