AC Motor 115volt help please
AC Motor 115volt help please
(OP)
Hello everyone,
I bought for ebay a electric motor 115volt 1hp single-phase 1625rpm. It has 2 capacitors. When I plug the motor to the 115v the motor hums and the shaft do not turn. One more thing when the motor is connected to the 115V it is imposible to turn the shaft manually and when the motor is not connected to the 115V I could turn the shaft manually.
What I should do???
Please see in attachement the url for the picture of that motor
Thanks
I bought for ebay a electric motor 115volt 1hp single-phase 1625rpm. It has 2 capacitors. When I plug the motor to the 115v the motor hums and the shaft do not turn. One more thing when the motor is connected to the 115V it is imposible to turn the shaft manually and when the motor is not connected to the 115V I could turn the shaft manually.
What I should do???
Please see in attachement the url for the picture of that motor
Thanks





RE: AC Motor 115volt help please
Scott
I really am a good egg, I'm just a little scrambled!
RE: AC Motor 115volt help please
By now the starting winding may be burnt out. Bad caps or a faulty start switch or relay won't generally lock the rotor. That is either contact between the rotor and stator or magnetic dust. Grinder motors are particularly susceptible to magnetic lockup when someone cleans up with an air hose and blows grindings into the motor. An ODP is a good candidate.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: AC Motor 115volt help please
My bad, I neglected to consider the "locked rotor" condition before replying. Thank you for pointing this out to me.
Cheers,
Scott
I really am a good egg, I'm just a little scrambled!
RE: AC Motor 115volt help please
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: AC Motor 115volt help please
Thanks for your help. I don't think that I have a bad bearing because I'm able to spin the shaft with my hand. The issue is only when I plug the motor to the electricity, the motor hums and the shaft did not turn even if I tried to turn it with my hand. It seems to me that the magnetic field lock the rotor. I open the motor and clean the rotor, but I have the same issue. May someone explain to me why there are two capacitors 65uf 240v 50-60hz, normally one capacitor for the start the second one is for what? One more thing I am in Canada we have 120volt 60hz ac.
Thanks for your help.
RE: AC Motor 115volt help please
There are several types of 1 phase motor designs out there, you most likely have what is called a Capacitor Start-Capacitor Run version (two caps). It has a centrifugal switch inside of it that allows the starting cap to be in the circuit to get the motor spinning, then the running caps keeps it spinning. If the switch failed to re-close after it last was used, the motor will not start and you get the condition you have observed. Either take it to a motor shop to have the switch repaired or you can try to do it yourself, but you will have to find the parts, which may be difficult for the average person.
Google is your friend. Good luck.
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RE: AC Motor 115volt help please
http://www.smokstak.com/forum/forumdisplay.php?f=6
RE: AC Motor 115volt help please
I don't understand how metallic shavings might cause this, I'd be interested if there is an explanation.
One thing that occurs to me is the rotor is severely off-center (or loose bearing clearance) and when energized the rotor pulls hard over against the stator. I have a hard time coming up with any other scenario.
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(2B)+(2B)' ?
RE: AC Motor 115volt help please
RE: AC Motor 115volt help please
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(2B)+(2B)' ?
RE: AC Motor 115volt help please
RE: AC Motor 115volt help please
The motors I suffered were three phase motors and they would lock up and turn at a fraction of an RPM whenever they got steel dust inside.
sniperam: Inspect the rotor and the stator for signs of rubbing or contact.
Try spinning the motor and then energizing it while it is spinning.
Check the bearings for play, especially upwards. Wipe rotor and the inside of the stator with a soft cloth and look for any iron dust on the cloth.
Read fast.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: AC Motor 115volt help please
Thank for your help
RE: AC Motor 115volt help please