Re: Ace Hardware grinder Sync conversion?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: FutureT@xxxxxxx 

In a message dated 7/18/05 7:17:11 PM Eastern Daylight Time, 
tesla@xxxxxxxxxx writes:


> Consequently, I was wondering if a relatively new 3450 1/3 horse
> power 3.5 amp inexpensive grinder from Ace Hardware (China) could be
> converted to a 3600 synchronous motor. There is no endplay and it
> runs smooth. As this may be temporary, I don't want to fiddle with
> phase control and such and am willing to make a few starts to get on
> the AC peak.


Jim,

I'm assuming this is a standard induction motor.
You can modify the motor to run synchronously, but it will
always start up in the the same phase position.  I'm not sure
what you mean by making a few starts to get it on the AC
phase peak.  If you mean that you'll make a trial run, and
then rotate the rotor on it's shaft to a new position and try
it again, and keep repeating this until best sparks are obtained.
Then, yes, this will work.  But if you mean that you want to just
try flicking on the power switch to eventually hit the right phasing so
to speak, that won't work.  It's only the hysteresis motors that
are capable of phasing in on various phase positions at start up.
A modified motor will become a salient pole type and require
an actual mechanical or electrical phase shift.  Once it's phased
in though, then it can be left that way.

Cheers,
John