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Re: Unexplained arcing current
Hi Gary,
> >>Tonight I shorted my gap, essentially shorting the NST, but having the
> >>current pass through my RC network. My R's are each 1.6K, 113W, non-
> >>inductive. C's are 450pF. Metering the current, I got 73mA (mine is a
> >>15KV/60mA NST), and the resistors barely got warm.
> >>
> >>Next I removed the short across the gap but broke the connection between
> >>the tank L and C, so that the gap arcs, but no cap charging/discharging.
> >>Now the resistors get hot as a pistol in no time. I tried measuring the
> >>current to the gap, but my digital meter just wigged out, I'm probably
> >>lucky it still works.
> >>
> >>So, what's different that causes the R's to see so much more power going
> >>to an arcing gap? It's just down to 60 Hz stuff now.
I have a few questions to your setup & the experiments above:
1.) Did you completely disconnect the primary in your second test? Or did
you just remove the wire going from the main gap to the primary cap?
Did you remove the RF ground wire connecting the secondary to the
center tap of the safety gaps and NST during the test?
2.) Have you ever tried inserting two additional resistors between
the safety gaps and the 450pF bypass caps? For a time limited
test you wouldnīt need super high wattage types. To make true
I^2*R comparison you would need to use (4) 800ohm types
instead of the two 1.6kohm you are using now.
3.) What exactly are your 1.6kohm/113W resistors made of?
Iīm asking because you wrote "non-inductive type". Every wire
wound resistor has some kind of inductance. Are they perhaps
carbon film? This might explain why they donīt get hot in a dead
short (only the current flowing), but heat up as soon as they have
to handle the high voltage.
These are just some wild thoughts without 100% scientific
reasoning behind them, but maybe it is of some help.
Coiler greets from germany,
Reinhard