Printable View
Hello,I have a GE (early 80's) A/C unit with the condenser fan running, but very slow RPM. It is kicking out with the high pressure switch. I removed the motor and capacitor but I am unsure of exactly how to test either of these items. any procedures would be appreciated. I have both a digital Volt/ohm and a Simpson analog meter. GE motor MOD#5KCP3966J215S, 1/4 H.P ,230V single phase 60 HZ , 1625 RPM ,1.30 amps. Thank you, Dave r
[Edited by pontiaction on 05-08-2005 at 05:03 PM]
Dave you could check the capacitor with simp meter,but the
only thing it will tell you is if the cap could take a charge it wont tell if it can hold a charge.
So a capacitor tester would be the best bet.
As fars as the motor again using ohm meter wont tell you the whole story.it best to have a megaohm meter so you can tell if the winding have been abuse from over heating.
Amp meter would be good if you have one,but I see you did not mention one.
It would be cheaper to call someone that has this equipment that could give you a true answer.
Hi Dave, you came to the right place.
The motor needs three things in order to run properly.
It needs 230 volts across the two leads which are marked common and hot.
This might be a white and black wire coming out of your motor.
Next it needs a run capacitor to split the phase between the run and start windings.
This might be two brown wires coming out of your motor.
Caps usually swell and or get oily when they go bad.
Last but not least is the bearings. They need to spin freely and without issue.
If your motor is running real s l o w .... it may be the capacitor.
You can have it checked at a local motor shop. Unless your digital meter has that feature built in.
I trust this helps you.
Thanks everyone for the quick responses. The motor has four wires a Black, Brown, Purple and green ground wire.
Black -- is line voltage directly into the motor from a contactor.
Purple -- from motor to capacitor
Brown -- from motor to other side of capicitor
Green -- from motor frame to ground
I tested all three wires for shorts to the frame and there are none.
I tested the A/C voltage at the disconnect and I had 115 on each leg (Which I think is right)
Thanks again everyone!
[Edited by pontiaction on 05-08-2005 at 05:36 PM]
Ouch! :(
Oh and it does spin freely, no bad bearings detected but there is quite a bit of endplay in the armature or bearings.
You either are getting only 115V to the motor &/or a bad run cap. that's bad. To check voltage put one lead from your meter to the line side of the contactor & the second lead on the other line side of the contactor. If you have a reading anywhere from 204V to 250V you're good.
But if the capacitor is wrong you'll need a real professional to come out & confirm that for you. Besides, you're not gonna be able to buy a cap. from your local Home Depot or Lowe's.