Re: synchronous motor

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: FutureT@xxxxxxx 

In a message dated 1/28/07 12:28:10 AM Eastern Standard Time, 
tesla@xxxxxxxxxx writes:

> I am looking for a low cost 1800 rpm synchronous motor.   Can anyone
> point me in the right direction?


One approach is to modify a regular 1725 rpm induction motor to
make it synchronous.  This involves grinding or filing 4 flat areas
on the armature (rotor).  These motors can be obtained free from
junked products.  But sync motors can sometimes be obtained
cheaply and this avoids the work of modifying the motor.  For
best results (assuming you plan to build a sync rotary spark
gap for a Tesla coil), use a salient pole, or reaction sync motor,
not a hysteresis type sync motor.  The hysteresis type motor
will sync at different phase positions each time the motor
starts which makes it inconvenient for phasing adjustments.

John