Re: SRSG Phase Relationship

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 3/2/02 12:26:22 AM Eastern Standard Time, tesla-at-pupman-dot-com
writes:


>
> Is there anybody in the group who can advise me on the pitfalls or
> successes of running a SRSG at 120 bps with a resonant tank cap?
>
> Thanks,
> Dave


Dave,

Yes, the 90 degree phase shift must be considered, and as you
said, the firing should occur somewhere around the zero crossing
point of the incoming AC.  As long as you have a safety gap in
place, you don't need to worry about destroying anything if the
phase is incorrect at first.  It's nice to use a remote phase shifter
circuit too, such as shown at my website at:

  http://hometown.aol-dot-com/futuret/page3.html

The way I set up the phase is very simple.  I don't do any
special setup ahead of time.  I just turn up the variac slightly,
and start twiddling the remote phase controller knob.  When
the gap starts firing, I raise the power a little and twiddle the
phase knob some more.  I keep doing this until I have full
power with best phase.  If things are not right at any point,
the safety gap fires, and no harm is done.  

I did run an NST system close to resonant for some time,
but switched to LTR to protect the NST.   I often use resonant
charging with potential xfrmer systems.  I use 120 bps most
of the time, because it seems to be more effective at producing
longer sparks from a given power input. 

Cheers,
John