Re: Motor Phase Controller problems

["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 9/2/02 11:39:54 AM Pacific Daylight Time, tesla-at-pupman-dot-com
writes:


>
> I'm currently using John Freaus simple motor phase controller basically
> using my variac and a capitor (simple LC phase-shifter) circuit, but have
> been getting the following problems:
>
> I currently am getting about 45 degrees of adjustable phase shift.  However,
> when I try to go beyond that, the motor simple looses locks, slows down, and
> eventually stops.
> I am currently using a 2A variac (small one) and tried a variety of
> different capacitor sizes, but can't seem to get rid of this problem.
>
> Could it be my variac is too small (inductance values too small???)
>
> Thanks
> Dan




Dan,

Have you measured the voltage across the motor over the full range of the
variac?  It should show a small rise in voltage (like around 5 volts) if the L
and C are chosen correctly.  I used a 10 amp variac and (from memory) around
200 ufd in capacitance for an 1800 rpm 1/3 H.P. sync motor.  If you want the
exact capacitance value that I used, I can look it up.

Ed Sonderman