Re: Bypass caps and Neons *NEEDED!* (fwd)

---------- Forwarded message ----------
Date: Mon, 15 Dec 1997 22:31:14 -0800
From: Bert Hickman <bert.hickman-at-aquila-dot-com>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Bypass caps and Neons *NEEDED!* (fwd)

Tesla List wrote:
> ---------- Forwarded message ----------
> Date: Mon, 15 Dec 1997 16:23:26 EST
> From: Esondrmn <Esondrmn-at-aol-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Bypass caps and Neons *NEEDED!*
> In a message dated 97-12-13 20:55:16 EST, you write:
> - snip -
> <<    I neglected to mention, safety gaps across the primary
>  cap IMHO is a BIG NO NO, safety gaps go from the
>  transformer end bell to ground, a gap across the primary
>  cap places a SMALL inductance directly across the
>  primary cap and when it fires results in a ring frequency
>  of 5-15 mhz or higher of very high current that is coupled
>  to NOTHING,  deadly for capacitors.
>  Mark Graalman
>   >>
> Mark,
> You say a safety gap across the tank capacitor is a bad idea?  After blowing
> two C.P. caps, it was suggested by at least a few folks on this list that I
> add a safety gap across the cap to protect it.  I am using a 14.4 kv pole pig
> running at 5 to 8 kva.  The gap is currently set at 5/8" and fires like a
> rifle when I try to put too much power into the system.  The gap uses #10
> solid copper wire bolted directly to the capacitor terminals.  The gap ends
> are bent into 1.0" diameter circles and soldered and de-burred.
> I would like to hear other folks opinion on this subject.  I believe both Mr.
> Cox and Malcolm suggested the addition of the safety gap across the cap.
> Malcolm, you have the same C.P. caps that I have.  What kind of safety gap do
> you use, what transformer voltage, and how far do you open the gap?
> Ed Sonderman

Ed and Mark,

One of the better reasons for having a safety gap across the cap is to
provide a path to ground at a breakdown voltage (hopefully) that's less
than the breakdown voltage of the tank cap when you happen to get a
streamer hit to the primary circuit...

-- Bert --