Re: Problem with Synchronous Motor and Timing Light

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

Original poster: "D.C. Cox by way of Terry Fritz <twftesla-at-qwest-dot-net>" <resonance-at-jvlnet-dot-com>



Mark the rotor and motor shaft with a small dot.  Perhaps your finger
pressure caused the rotor to turn slightly on the motor shaft.

Dr. Resonance




----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, August 16, 2002 7:14 PM
Subject: Problem with Synchronous Motor and Timing Light


> Original poster: "Daniel McCauley by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <dhmccauley-at-spacecatlighting-dot-com>
>
> Okay, so I picked up a strobe light from Radio Shack this evening and with
> Terry's modifications, made me a 60Hz timing light.
>
> I got my SRSG and the timing light, turned the lights off, and tested
away.
>
> However, I do not know too much about how synch motors really work, but
here
> were my results:
>
> 1.  The timing light worked great.  Basically froze the rotor to free time
> so you could see the position of the rotor in respect to the 60Hz input
> power.  However, the problem is that if I briefly touched the side of the
> rotor to slow it down just for an instant (yes, it does burn my finger),
the
> rotor locks in speed again, but in a slightly rotated position and will
> continue to move about everytime i slow it down for an instant.  Is this
> normal for a synchronous motor???  I was under the impression that once
> attached securely to the shaft that it would maintain its relative
position
> forever unless you rotated the rotor about the motor axel.  What are your
> thoughts??
>
> Thanks
>
> Dan
>
>
>