Re: Voltage multiplier capacitors (fwd)

["High Voltage list" <hvlist@xxxxxxxxxx>]

Original poster: Steven Roys <sroys@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Tue, 10 Apr 2007 18:07:29 -0700
From: Ed Phillips <evp@xxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>, Ed Work <edward.phillips@xxxxxxx>
Subject: Re: Voltage multiplier capacitors (fwd)

High Voltage list wrote:

>Original poster: Steven Roys <sroys@xxxxxxxxxx>
>
>
>
>---------- Forwarded message ----------
>Date: Tue, 10 Apr 2007 12:01:33 -0700 (PDT)
>From: Chris Roberts <quezacotl_14000000000000@xxxxxxxxx>
>To: High Voltage list <hvlist@xxxxxxxxxx>
>Subject: Re: Voltage multiplier capacitors (fwd)
>
>So I just recieved the caps from ebay and am pretty ready to build this, only now I am worried about killing my nst with resonant rise. (NSTs keep getting harder to find) Would a tripler using 3300pf caps present a problem? Would there be any easy way to prevent this from happening? I might try something as simple as a saftey gap, yet if there is a better way to prevent this I would like to know...
>
>High Voltage list <hvlist@xxxxxxxxxx> wrote:  Original poster: Steven Roys 
>
>---------- Forwarded message ----------
>Date: Fri, 23 Mar 2007 15:40:15 -0700
>From: Ed Phillips 
>To: High Voltage list 
>Subject: Re: Voltage multiplier capacitors (fwd)
>
>
>I've run Electronic Work Bench (spice derived) simulations in the past to study an inductive NST running a capacitive voltage multiplier. Can't find the files but remember that I suspected it might be possible to get into resonant voltage rise problems and that one should use care in trying the idea. Has to work for small capacitors of course but when they get into the 0.01 ufd region and above (to improve regulation) trouble may be brewing.
>
>Ed
>
     I can't see any problem with that low a value although I ALWAYS 
recommend a safety gap.  I'm at home today and the simulation is on my 
system at work so can't quote anything more but will try to get a chance 
to take a look tomorrow.  My calculations were for a 15 kV, 60 ma 
transformer.  If yours is significantly different ( lower voltage and 
lower current) you might see approach to resonance at lower values of 
capacitance but the safety gap should protect you no matter what.  If 
you get a chance send me the ratings on your transformer both to this 
address and the ngc one.

Ed