"NSM" writes:

"Sam Goldwasser" wrote in message
...

| Physically it looks fine. It's not that important to spend time on
| at this point. I picked up another grinder for $6.
|
| Probably no need to put it in an oven. Just run it up a couple times
until
| it fails and let it cook in that state. Then pull the rotor and test.

It sure sounds like it's pulling out of sync, so there's no out-of-phase
current to keep it running. Does it have a capacitor?

No capacitor. Split phase meaning two windings, one with much higher
resistance to produce the phase shift.

The thing is, it's not only stopping. It acts as a very good brake
when the condition occurs - hard to turn. This unlike an induction
motor with only one winding energized which will turn freely and
then spin up to normal speed once its going fast enough. This one
will slow down if you try to spin it by hand. Then make a loud hum
or buzz at a certain angle of the rotor.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
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