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johnmorely
Jul 19, 2012, 06:49 AM
Hi
I have a 1.5 hp compressor motor that blows breakers: motor runs then centrifugal switch kicks in and motor blows breaker (15A). Replaced capacitors. Suspect problem in primary winding. When wiring reversed (ie running winding now start winding and vise-versa) starts and seems to continue running ; however when put under load motor looses power as compressing in tank increases.
Q: can the problem be traced and eliminated without replacing the motor? That is, can I eliminate just the part of the primary winding that's shorting? Or is this just to difficult.

tkrussell
Jul 19, 2012, 06:59 AM
Cannot eliminate part of a winding in a motor.

I have to assume this 1.5 HP motor is a single phase 240 volt motor, which should draw 10 amps +/-.

Best to have the motor either replaced or sent out to a motor shop for re-winding.

johnmorely
Jul 19, 2012, 08:13 AM
Thanks. That's what I thought. Since the motor runs briefly (blow breaker after 5-15 seconds after cent switch engages) Is it possible to use pulse-width modulation or pulse-duration modulation to keep the motor from drawing too many amps?

johnmorely
Jul 19, 2012, 08:43 AM
More specifically: a dimmer switch to limit current draw to 15A or less. Since I only usethe compressor briefly (air ratchet, etc.) could this work without replacement/new winding?

Missouri Bound
Jul 20, 2012, 01:15 PM
You are joking, right? Replace the motor or the compressor. Invest in a clamp on ammeter.