Re: Can anyone explain this???

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

Original poster: "Scott Fulks by way of Terry Fritz <twftesla-at-uswest-dot-net>" <darkthing-at-earthlink-dot-net>

>From your website, I assume you have not yet added the main MMC, and so are
testing your transformer and spark gap alone.  If you have the main
capacitor installed, my analysis below will not make much sense.

The addition of the transformer bypass caps to ground will boost the spark
output because they act as a discharge cap.  Basically you just built a
mini-MMC of 4x500pF caps in series-parallel, giving you 500pF across the +
and - outputs of the transformer (the fact that the center of the cap array
is grounded is irrelevant).

I'd guess that the 30-to-38 amp power jump is due to the hotter gap.
According to an old spark-gap radio manual, the resistance of a gap is
reduced when more current flows across it.  The discharge of the 500nF
capacitor will give you much more instantaneous current than the direct
400mA output of the transformer, so the gap will have a lower resistance,
drawing more tranny current.

I don't know whether this can hurt the transformer, but it doesn't sound any
more strenuous that the actual coil operation will be.

Regards,
Scott Fulks (darkthing-at-earthlink-dot-net)

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, April 12, 2001 7:19 AM
Subject: Can anyone explain this???


> Original poster: "Tyler Steineckert by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <tsgeoman-at-qwest-dot-net>
>
> I am getting very close to completion of my huge coil.
> Today I put some small caps on my transformers because I was told by
fellow
> coilers that it would help to protect them.  What I did was to put 4
500pf
> 20kv caps, putting two on each side of the tranny, to ground. The tranny
is
> two modified NST to run 12kv 400ma.
> Then just for fun, as I have done before, I ran up the roto and gave it
some
> power.
> Sudenly the power output of my tranny seemed to double.  There were huge
> sparks coming from the roto. I thought it was a phase problem but as I
> adjusted the phase of the motor the sparks got even bigger and started to
> fire the safety gap on the trannys. Then I noticed that the power pull
went
> from 30 amps to 38 amps.
> I got an 8 amp jump, just adding these caps.
> Not that any of this is bad. It just suprised me to se such a power
increse
> in input amps as well as visiual output from the trannys by just adding
> these small caps.
> Have I done something wrong?
> Is the power increse going to hurt my trannys?
> Any coments would be greatly appreciated.
>
> Thanks all,
> Tyler
> P.S. You can see pics of the entire coil setup as well as the new caps
that
> I put on at my web sight under TRANNYS on my 3rd coil.
> www.users.qwest-dot-net/~tsgeoman/coils.htm
>
>
>
>