Re: sync motors - update

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Esondrmn-at-aol-dot-com>

In a message dated 1/30/02 7:30:53 AM Pacific Standard Time, tesla-at-pupman-dot-com
writes: 



>
> I just tested the sync motor conversion with a modified strobe light setup, 
> running exactly in sync with the AC line, and it appears that the motor is 
> slightly slower than 3600 RPM.  It was rated at 3400 RPM, and appeared to be 
> running at 3600 as far as I could tell, until I used the strobe.  The mark on
>
> the shaft that I made turns backwards from the normal direction of spin at 
> about 1, or a little less, RPM.  I tried best I could to put a load on the 
> motor (just the shaft sticking out), and it didn't seem to change at all. 
> Anyone have any ideas what's going on?  Do I need to make the flats in the 
> armature bigger?  I noticed in the "plans" at 
> <http://hot-streamer-dot-com/TeslaCoils/Misc/syncmot.zip>http://hot-streamer.co 
> m/TeslaCoils/Misc/syncmot.zip, it says 1750 or 3450 RPM, my motor was 3400 
> RPM - 
> does this make a difference?  It is an induction motor - nothing on the 
> armature, and two field windings, with 2 starting coils.  Should the
> sstarting 
> be disconnected? (I haven't yet).  Thanks! 
>
> --------------- 
> Sean Taylor 
> The Geek Group 



Sean, 

It would be interesting to use a variac to power the motor and slowly increase
the voltage to see where it actually locks into sync.  Measure the voltage
right at the motor leads.  It would be good if the variac would go up to about
130 volts. 

Ed Sonderman