Re: switching options for huge cap discharges (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Sat, 14 Jul 2007 13:28:54 -0500
From: resonance <resonance@xxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: switching options for huge cap discharges (fwd)



We use National 7703 Ignitrons, 20 kV standoff and reliable switching of 
45,000 Amperes.  Trigger is with a simple 2 kV DC cap, 2 uF rating.  We use 
a 850 TV type power supply xmfr with voltage doubler and then switch thru a 
standard Hg relay.  Works fine if you keep the relay on an insulated post or 
chuck of phenolic.  Rell has them new for around $1,100.00.  I have them 
used, cheap.

I have some used ones in stock if you need one or two.   Contact me 
off-list.


Dr. Resonance
Resonance Research Corp.
www.resonanceresearch.com


----- Original Message ----- 
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Saturday, July 14, 2007 7:57 AM
Subject: switching options for huge cap discharges (fwd)


> It is a little OT.  Please reply directly or use the hvlist.
>
> Chip
>
> ---------- Forwarded message ----------
> Date: Sat, 14 Jul 2007 05:02:27 +0000
> From: David Rieben <drieben@xxxxxxxxxxx>
> To: tesla@xxxxxxxxxx
> Cc: drieben@xxxxxxxxxxx
> Subject: switching options for huge cap discharges
>
> Hi all,
>
> This may start to get a little border line OT but I was hoping to get some 
> input
> on this. I am now in the process of trying to reconstruct my quarter 
> shrinker
> cap assembly and the only thing that is really giving me a fit is how to 
> safely
> and reliably switch the 10s of thousands of amps from the discharge of a 
> 15
> to 20 kJ capacitor bank. I've done this some before in the past but the 
> huge
> currents systematically melted and destroyed the 1 1/4" square brass con-
> tact blocks after a few dozen shots. I noticed Ed Wingate used a drop 
> switch
> mechanism that utilized what looked like about 1/2" diameter tungsten rod 
> con-
> tact points to switch the huge currents. 
> http://www.tb3.com/tesla/ratcb2005/pages/IMG_3997.html
> What about triggered spark gap firing for this purpose? I'm sure that just
> as in a Tesla coil SG, tungsten is the superior metal of choice for 
> quarter
> shrinker switch contacts as well. If anyone has experince along these 
> lines
> and would like to share their experiences with me, I would be most 
> grateful ;^)
>
> David Rieben
>
>
>