Re: Variable current controls & chokes

to: Mike

This concept works --- "sort of".  If you get too much current across too
small a section of the winding you can smoke the variac you are using.  A
better design would use a series reactance with taps and then run this in
series with your "current variac" to allow a range of adjustment.  Sort of
like running a pot output in series with a fixed resistance to prevent it
from accidently hitting a range that would draw too much current on a low
resistance pot.



-----Original Message-----
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Friday, June 25, 1999 7:15 PM
Subject: Variable current controls & chokes

>Original Poster: "Michael J. Veach" <veachm-at-sunyit.edu>
>I am working on a new driver and was wondering about using large
>variacs as variable current chokes. I want to be able to adjust my
>current between a minimum value and a maxinum set value. I was thinking
>of a large variac in series with a choke made from another variac, and
>these in series with the transformer. Since I have never made a current
>limiter before (I usually use neons), I'd like to get the advice and
>imput of the list members, and maybe some help with the design for this
>current limiter. Any hints and tips, or instructions on how to modify
>and rewind the variacs, would be a big help. I know they need to have a
>slot cut into the core, but should I make it a certain size? I am
>planning on using a 14.4 kV pig in case you need to know.
>Thanks in advance,
>Mike Veach.
>P.S. I am also interested in any info you may have on Cockraft-Walton
>multipliers. You can reply to this off-list at my email addy, which is