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Cap discharge time: was: Re:NEW break-rate/power tests

Hello John, all

John wrote:
"I placed the (2) 7200 volt transformers in series, so my voltage
is still 14.4kV, the same as with the one transformer.  I'm sorry
if I didn't make this clear enough.  If I had actually used 7200
volts, I would have had to increase the cap size by four times to
keep the power input the same at a given break-rate."

Yeah, sorry about that one. I guess the words "to make a
stiffer psu" caught my attention, so I assumed you had
wired them in parallel. I know, wiring two 1500VA in series,
also makes the psu stiffer. Of course, I should have realized
this, just by looking at your cap values. I just didnīt read it
right (:o( .

I wrote:
> I also think the low voltage,
> high current setups benefit from the high Lsec to Lpri ratios.
> I know resonance believers wonīt like this, tho :o).

John wrote:
"High ratios are good, but I acheive them by using a lot of L in
both primary and secondary.  This reduces my relative gap losses."

Okay, but wouldnīt an ultra high impedance value
on the secondary side have a harder time charging
Ctop (The higher the impedance, the lower the
charging current)?

I wrote:
> Might it be possible that it has something to do with the
> cap DISCHARGE time? In a high break rate system one
> should consider that not only does the cap have very little
> time to charge (which is why the cap value has to go down
> for a given xformer VA rating at higher BPS values), but it
> also has very little time to discharge.?!?

John wrote:
"I don't see how the break-rate would affect the cap discharge
time in a typical TC."

Hmm, let me try an analogy (even if it isnīt a good one):

Take a cap and charge it to "x" volts. Then take a piece
of wire and short it for, letīs say, a minute, all the stored
energy (in the cap) will have been used up (turned into
heating the wire in this case). If you remove the wire
and take a DMM to measure the voltage, it will read
zero or almost zero volts (no surprises here). If you now
repeat the experiment, but this time only "brush" the
wire against the cap terminal, you will find that the cap
has residual voltage on it.

Taking this to Tesla coils:
A low break rate will allow the cap to discharge (more)
fully than a high breakrate system. Meaning the lower
bps setup might be able to transfer more power
(because the cap has the time to discharge fully).

Coiler greets from germany,
Reinhard