RE: Phase adjust

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

Original poster: "Basura, Brian by way of Terry Fritz <twftesla-at-uswest-dot-net>" <brian.basura-at-unistudios-dot-com>

John/all,

I've been sick with the flu so my measurements from yesterday were suspect.
Therefore I sat down today and methodically measured and documented each
configuration. I found that the lack of phase shift I was seeing yesterday
was due to overcompensation (too much capacitance). I also question my
setup yesterday so please disregard the numbers from my previous post.

Today's setup used a W10 Variac, various combinations of motor run caps,
and 12" rotor with eight 1/4" electrodes. Neither of my motors uses a run cap.

With the 1800rpm 1/2hp motor 180ufd was the optimal value. This provided a
full 45-degrees of adjustment, 2-volt change over the Variac's range,
smooth operation, and very little braking after the power was removed. A
smaller capacitance (135ufd) caused the voltage to plummet and the motor to
loose sync as the inductor (Variac) was adjusted. A larger capacitor
(203ufd) worked but the resonant rise was over 10-volts, the motor did not
run smoothly, and there was two times during the spin down when there was a
pronounced braking. Higher capacitance caused resonant rise in the 25+ volt
range, surging, and NASTY braking issues when the power was removed.

With the 3600rpm 1/2hp motor 270ufd was the closest to optimal I could
obtain with the caps I had on hand. This configuration provided a full
90-degrees of adjustment, 2-volt change over the Variac's range, and smooth
operation. However there was some braking during spin down and it looses
sync if the Variac turned past 75%. This leads me to believe I'm close to
the correct capacitance but not quite there yet. A smaller capacitance
(202ufd) caused the voltage to plummet and the motor to loose sync as the
inductor was adjusted. A larger capacitor (338ufd) produced a resonant rise
well over 15-volts and there was a point during the spin down when there
was a pronounced braking.

The only currents I measured were on the 3600rpm motor. Mains current
without the phase adjuster was 8.1amps. With the 270ufd phase adjuster the
mains current ranged from (min to max inductance) 4.4 to 3.4amps, motor
current ranged from 8.3 to 10.2amps, and the capacitor current ranged from
11.4 to 13.1amps.

My current plan is to test this next week on my 6" coil then package it
incorporating a time delay relay to switch the phase adjuster into the SRSG
circuit after the motor has time to spin up. 

Hope this furthers the cause.

Regards,
Brian B.