RE: synchronous motor

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Anthony R. Mollner" <penny831@xxxxxxxxxxxxx>

Hi to the both of you,
  Your comments are invaluable to me. You make me wonder if I can utilize
either winding? May I ask the question about wiring them? It sounds to me
like the run, start and starter capacitor needs to all be switched on at the
moment that it's turned on and than the start and winding and capacitor are
than disconnected, leaving the running winding on. Is that the how it needs
to be connected? I have a fully built propeller gap with a blower and
everything, ready to be fired up now, except for the final motor wiring!
Thanks for the help!

Tony

-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx]
Sent: Saturday, February 10, 2007 8:29 PM
To: tesla@xxxxxxxxxx
Subject: Re: synchronous motor


Original poster: FutureT@xxxxxxx

In a message dated 2/10/07 7:33:26 PM Eastern Standard Time,
tesla@xxxxxxxxxx writes:

>Hi Anthony,
>
>You might try to measure the resistance of the two winding.  If both
>windings are the same guage and the same resistance, it might not
>matter which one you use for the start winding.  Leaving them on all
>the time may harm the start capacitor.  I dont think they would fight
>each other since one has a different phase from the other (due to the
>capacitor) and syncing is not an issue unless you modify the motor
>for sync operation.  If you experiment with the windings, you may
>want to fire up the motor for a very short time, power down, and see
>if the windings are getting warm.  Repeat this for progressively
>longer times until you are satisfied the motor is running
>properly.  If you suspect it is not right, you may want to swap the
>two windings and try again.
>
>Gerry R.


Gerry, Anthony,

If Anthony's motor is like the one I tried, I found that the motor
never synched if the start winding remained connected.  It was
a 1/10 or 1/12 HP motor.  It had the special current-switch for
disconnecting the start winding as the motor came up to speed.
If I remember correctly, I was able to determine which was the
main winding by measuring its resistance as you suggested.
I think this motor used an 85uF start cap, or something similar.

John