Re: Marx generator (fwd)

[<sroys@xxxxxxxxxxxxxxxxx>]

---------- Forwarded message ----------
Date: Mon, 27 Sep 2004 12:39:11 -0500
From: Dr. Resonance <resonance@xxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Marx generator (fwd)


The diodes blew because he didn't do the math.

Each diode string has to be rated at 2.8 for peak reverse voltage.

With 15 kV Erms, then 15 * 2.8 = 42.5 kV.   We use 9 kV Fujitsu 300 mA
diodes, so we would use a minimum of 7 diodes per string (safety factor
also).

Be sure to use an inductance in series with the output and a resistor plus
inductor on the charging power supply in case the unit "prefires" while
charging.  This happens when you are setting up your initial sparkgap
settings.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913

>
> He is using a 15 kV tranny, but the full bridge rectifier he has
> built, has only 12 diodes 1N4007 per leg. They are shunted by
> standard 0.5 W resistors (unnecessary, I know) and of course some of
> them burnt. So did many diodes.
>
> This is an interesting matter and maybe I'll build a Marx some day as
> well.
>
> Herwig
>
>
>
> ---------------------------------------
> Greed is the root of all evil!
> ---------------------------------------
>
>
>