Re: phase shifter with run-cap sync motors

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

Original poster: "Metlicka Marc by way of Terry Fritz <twftesla-at-uswest-dot-net>" <mystuffs-at-orwell-dot-net>



Tesla list wrote:

> Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<FutureT-at-aol-dot-com>
> john, all

the 180 shift was measured with my scope, that's why i called electrical
shift. i
believe terry put the scope pics on hot streamer? i haven't checked with a
strobe
but will try to get one to assemble asap.
the way i checked it was to hook channel two to the insulation (NOT THE
COPPER) of
the line and channel one to the insulation of load into the motor. this gave me
clean tracing at the full sweep of the variac showing all spikes on the wave,
nothing special so maybe more could try this to see if the electrical shift
corresponds to mechanical on there setups?
i DO know that the two traces are 180 DEGREES out of phase, not trying to
say things
work different in my shop then anyone else, just what i see.
will get back at it soon,
marc

>
>
> Marc, all,
>
> This motor behaviour is very similar to what Alan Jones has found,
> and is valuable info for those who are setting up their phase shifter
> circuits.  I must say though, that I'm not convinced that you are seeing
> 180 degrees of electrical shift (we spoke of this before).  I believe that
> this circuit cannot shift the phase more than 90 degrees electrical.
> I would wish that you are right about the 180 degrees, because it
> would make the phase shift system even better   :)   Certainly with
> a more complex circuit using separate stages, more than 90 degrees
> could be obtained however.
>
> I'll be looking forward to your further findings.
>
> I have not heard of anyone else seeing more than a 90 degree phase
> shift.  If anyone has, please let me know.
>
> Thanks,
> John Freau