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cedestech
04-04-2005, 04:16 PM
Will a bad cap or starter cause a induction motor to pull to much amperage?

Specificly I have a air compressor here that
the motor spins real slow then popps the breaker.

Every thing is very free mechanicaly.

?

cedestech
04-04-2005, 04:16 PM
Will a bad cap or starter cause a induction motor to pull to much amperage?

Specificly I have a air compressor here that
the motor spins real slow then popps the breaker.

Every thing is very free mechanicaly.

?

Bryan Norton
04-04-2005, 04:25 PM
Are you running a 220v system on 110v? If so double the rated amps.
I had an air compressor rated for 15 amps at 220v, but when running it at 110v (properly wired!) it pulled 30 amps, and at start up would blow the breakers.

Bryan Norton
04-04-2005, 04:25 PM
Are you running a 220v system on 110v? If so double the rated amps.
I had an air compressor rated for 15 amps at 220v, but when running it at 110v (properly wired!) it pulled 30 amps, and at start up would blow the breakers.

cedestech
04-04-2005, 05:01 PM
No, this is a generic 110v 3.5hp motored compressor.


There is the pressure cut off switch, a
RPM cut off switch in the motor, and
2 caps, one is smaller and labeled starter.

I do DC all day long but when those electrons go back and forth it all starts confusing me....

/ubbthreads/images/%%GRAEMLIN_URL%%/smile.gif

cedestech
04-04-2005, 05:01 PM
No, this is a generic 110v 3.5hp motored compressor.


There is the pressure cut off switch, a
RPM cut off switch in the motor, and
2 caps, one is smaller and labeled starter.

I do DC all day long but when those electrons go back and forth it all starts confusing me....

/ubbthreads/images/%%GRAEMLIN_URL%%/smile.gif

Buck Beasley
04-04-2005, 05:05 PM
I have this problem in my shop all the time. I finally solved it by lowering the start up pressure. Try bleeding off some pressure and see if that takes away some of the start up load. On high pressure dive compressors we used check valves and auto bleeders that purged the compressor when it shut off so it started at no load. Not sure who make this for lp compressors.

Buck Beasley
04-04-2005, 05:05 PM
I have this problem in my shop all the time. I finally solved it by lowering the start up pressure. Try bleeding off some pressure and see if that takes away some of the start up load. On high pressure dive compressors we used check valves and auto bleeders that purged the compressor when it shut off so it started at no load. Not sure who make this for lp compressors.

DMS Racing
04-04-2005, 05:07 PM
Check your unloader valve. If it isn't working properly, the compressor will see the tank pressure before it gets enough speed, using the starter capaciter to get over the transient voltage requirements, to get going, will then run slow and quickly pop the breaker. Also, how long a run from breaker to your plug where your comp is plugged in, and what size wire? Resistance in wiring can add to the problem, if it is too small and the run is too long.

Could be the pulley sizes between motor and 'pump'. Was it running OK and then started popping the breaker?

DMS Racing
04-04-2005, 05:07 PM
Check your unloader valve. If it isn't working properly, the compressor will see the tank pressure before it gets enough speed, using the starter capaciter to get over the transient voltage requirements, to get going, will then run slow and quickly pop the breaker. Also, how long a run from breaker to your plug where your comp is plugged in, and what size wire? Resistance in wiring can add to the problem, if it is too small and the run is too long.

Could be the pulley sizes between motor and 'pump'. Was it running OK and then started popping the breaker?

anthony c smith
04-04-2005, 05:42 PM
Most likely if it were running fine in the past it is the capacitor. If the run capacitor is bad then it will do exactly as you describe Emmit.
You can test it with a simple ohms meter.
give me a call and I will walk you through it. 512-760-6614. Anthony.

anthony c smith
04-04-2005, 05:42 PM
Most likely if it were running fine in the past it is the capacitor. If the run capacitor is bad then it will do exactly as you describe Emmit.
You can test it with a simple ohms meter.
give me a call and I will walk you through it. 512-760-6614. Anthony.

JesseJohnson
04-04-2005, 08:59 PM
Emmett, I just had the motor replaced in my home A/C. The cap tested out at 2.5k and was supposed to be 7.5k. Burned up the motor, motor made all sorts of weird noises, ran really hot, etc.

Anthony can hook you up.

JesseJohnson
04-04-2005, 08:59 PM
Emmett, I just had the motor replaced in my home A/C. The cap tested out at 2.5k and was supposed to be 7.5k. Burned up the motor, motor made all sorts of weird noises, ran really hot, etc.

Anthony can hook you up.

cedestech
04-05-2005, 08:10 AM
And we have a winner......

Per Mr. Smith the run cap is crap!

Thanks!

cedestech
04-05-2005, 08:10 AM
And we have a winner......

Per Mr. Smith the run cap is crap!

Thanks!