Re: Sync Motor :-( update_3

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Scot,

At 04:58 PM 7/31/2001 -0500, you wrote:
>
>Hi All...
>
>Im starting to wonder if one of the stator fields is shorted     warm to hot
>running  slow speed  "grinding" possible bucking .....
>
>Hmmmmmmmmmmm ...
>
>Scot D
>
>

Me too...  I am thinking I'll have to (if it comes down to sending it to
me) break each of the four stator windings and ohm them each and to ground
and  highpot test them.  If there is an intermittent short or open, that
may be the problem.  Could be as simple as a bad crimp connection too...
Even a broken bearing that is catching up could mess the motor up.  I hope
I can get to the short and fix it if that is the problem.  The mass
produced motors are a little hard to get inside for detailed stator work (I
think they use glue :-)).  A scope and a current probe will tell a lot in
this case.

I wonder if the motor has a "burned smell"?  An intermittent short could be
well hidden but there should at lest be a little smoke are electrical
burning smell.

This definitely looks like an "interesting" motor :-)))  Apparently, we
have all pretty much eliminated the simple problems and it may be time to
get some serious test equipment on the case!  It is supposed to just always
work just fine :-))  Aside from having a mill grab and destroy a rotor (it
is really hard metal), I can't remember a sync motor conversion ever going
bad...  Best not to start now ;-)

Cheers,

	Terry