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Re: 2 questions on resonance



In a message dated 99-04-09 05:00:58 EDT, you write:

<< >     With the larger capacitor mentioned by Gary and Terry, one must 
 >also get some partial cap charging after dwell as the transformer 
 >comes down off its peak but this time the larger capacitance taken 
 >with a limited energy delivery capability (which I think always 
 >exists) cannot cause Vcap to exceed the peak transformer voltage. 
 >With the gap set wide enough in the first case, I think you will get 
 >just as much energy in the cap as in the second, the disadvantage 
 >being the much higher voltage the smaller cap has to reach to reach 
 >the same energy storage. I still don't see any evidence that the 
 >transformer can do better than its faceplate VA rating. 
 >     The big cap idea sounds like it should be a firm recommendation 
 >for capacitor sizing rather than the now (apparently) dated notion of 
 >going for an Xl=Xc match. There is some inherent protection for the 
 >transformer built in by way of secondary voltage limiting per half 
 >cycle as a bonus.
 >
 >?
 >Malcolm
 > >>

Malcolm, all,

My latest tests, which I posted separately, support most of what 
you say above.  But I was only able to achieve it using a sync gap,
not with static gaps.  Maybe static gaps are too chaotic to permit
meaningful downside charging?

Regarding current draw, I had to turn up the voltage to 140 volts
input for the larger-than-resonant cap situation to obtain  620 watts
of current draw.  But the resonant charging situation drew this same
current input using only 120 volts input.  I'm using a 12kV, 30ma
NST (360 watt nameplate).

John Freau