Re: Dimmer as a Variac.

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

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

>
> You bet!  Running that little TO-220 thing into a highly reactive load
(but
> my coils are PFC corrected) with "strange things" being reflected
backwards
> from the spark gaps and all will be a "challenge" for the dimmer!! :-))
> There is also the radiated and conducted in noise and such that may affect
> their operation.  However, given the commodity pricing of the things,
there
> is plenty of room for added circuits if that will allow them to work.
> Right now I am just exploring the possibility without any great confidence
> that they can be made to work well.  However, if they could be made to
> work, it would be cool!
>
> Cheers,

The other thing to think about is converting the dimmer to a 3 wire hookup
(with a ground) rather than the series 2 wire hookup.  Instead of feeding
the RC phase shift network from the line in series with the load, feed it
across the line, so that the load is only in series with the TRIAC. In your
picture, it's hard to tell which cap you'd need to move.

By the way, the device in your dimmer is probably a "Quadrac" which is like
a Triac with a Diac in series with the gate. Teccor is a common mfr of
these. I can't tell from the picture whether it is a Teccor unit...