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William Noble William Noble is offline
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Default Jet 1442 Problem

if you think about it, the capacitor is across some windings to produce a
phase shift. Also, electrolytics have a pretty good leakage. Of course an
AC circuit can leave volts on a capacitor, it just depends where in the AC
cycle you turn it off - but I wouldn't worry - unplug and take it apart, by
the time you get it apart, the cap will be discharged. But, the cap is an
electrical part, it doesn't care about dust - you can pack it in dust and
nothing will happen unless the dust has a lot of water and shorts it out-
more likely welded contacts or dust keeping them from opening, or a broken
wire inside the motor.


"Joe" wrote in message
et...
Bill,

Thanks for the reply. Since it's a tefc, I was hoping to avoid what
you're suggesting doing, which is take it apart, but oh well. Guess
that's a project for tomorrow. Just how long do those capacitors hold a
charge anyway? Not looking forward to getting zapped.

jc

"Bill Rubenstein" wrote in message
. ..
Most likely -- your centrifugal switch is not opening. That switch is IN
the motor so it must be taken apart to get to it. Sometimes air through
the motor will do the trick but only sometimes.

If the start capacitor is bad (not very likely) it may not get the motor
spun up enough to kick the cent... switch. In this case you may be able
to spin it up by hand fast enough to kick it. That would prove that the
switch probably working right but the capacitor is bad.

If under warranty -- take it back.

Three phase motors don't have any of that 'stuff' which goes bad in
single phase motors. With the advent of less expensive vfds, somebody
needs to come out with a motor/vfd retrofit kit for various lathes for
those folks who are tired of screwing with capacitors and centrifugal
switches. That would also give you the low rpm and reversing which are
so sorely needed on so many Reeves drive equipped lathes.

Bill






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