On 2008-06-14, Ignoramus29659 wrote:
Some facts.

1. 5 HP Single Phase Baldor motor
2. Connected to compressor pump
3. Can be easily spun by hand, not stuck
4. Connected to 240v outlet (245 volts actual)
5. Used about 30 feet of 14 gauge cable
6. ** MOTOR BUZZES LOUDLY, DOES NOT SPIN AT ALL **
7. Incoming voltage at the switch close to motor about 216 volts
during starting/buzzing
8. I opened the cover covering capacitors.
9. Found two round/cylindrical start caps and one oval/cylindrical run cap
10. During starting, voltage on the RUN cap is 197 volts
11. During starting, voltage on the START cap is only about 15 volts

This seems to point me to direction that the contacts on centrifugal
switch may be bad.

Would love to get some quicky answer.



I continued based on assumption of centrifugal switch.

I opened the motor. It was very dirty inside. I think that it was
taken off a big grinder or something. But it did not look burnt.

Anyway, I cleaned centrifugal switch contacts with fine sandpaper.

Reclosed the motor.

After this I saw some signs of life, bits of movement but not much.

I then removed all drive belts and disconnected motor from pump.

The motor, now, spins at first slowly, then accelerates in 1-2 seconds
-- way too slow to be normal -- and then runs strong like a real
Baldor.

I also tried adding and removing starting capacitance, it did not seem
to make much difference.

I think that what I will do is

1. Take off the rear endbell again, and clean contacts some more
2. Try VERY carefully to measure resistance between them (hard to do)


--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/