Re: Is this motor synchronous?

From: 	FutureT[SMTP:FutureT-at-aol-dot-com]
Sent: 	Wednesday, December 31, 1997 12:56 PM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: Is this motor synchronous?

In a message dated 97-12-31 03:32:13 EST, you write:

> My 1725 RPM motor didn't have a cap, although I'm suspecting I might have
> been successful had I removed less material.  How does one determine _by_
> _observation_ if a motor is a capacitor start/induction run type of motor
> vs an induction start/ induction run or capacitor start/capacitor run
> type, short of having a spec sheet?
> Thanks again for the help.
> Gary Lau



I ground my flats for the 1800 rpm motor 1 1/8" wide for a 2 7/8" dia
armature if I remember correctly (I posted this info in the past).  I got
good results, so I suppose this ratio is OK.  I have no idea if there is
a better ratio.  My motor was a 1/4 HP washing machine motor with
no capacitor.  IMO, a .65 amp motor is somewhat weak for use in 
a sync-gap.  A 1/25 HP motor is probably a practical minimum unless
the rotor is tiny.

Cap start motors have a centrifugul switch inside, as do induction
start motors.  I think cap run motors tend to be small, less than
1/4 HP.  This is a rough guide as I'm not an expert on these various
motor types.  

Hope this helps,
John Freau