[Prev][Next][Index][Thread]

Re: DANS POWER SUPPLY

tesla-at-grendel.objinc-dot-com wrote:
> 
> >From kasper-at-exo-dot-com Mon Feb 26 12:12 MST 1996
> From: kasper-at-exo-dot-com
> >Received: from server.snni-dot-com (root-at-server.snni-dot-com [165.113.174.1]) by uucp-1.csn-dot-net (8.6.12/8.6.12) with ESMTP id LAA14347 for <tesla-at-objinc-dot-com>; Mon, 26
> Date: Mon, 26 Feb 1996 10:06:56 -0800
> Mime-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Subject: DANS POWER SUPPLY
> To: tesla-at-objinc-dot-com
> 
> Scott:
> 
> The first thing on the left in series with a resistor (LP1) is supposed to be a
> neon light bulb.  The other 2 things (J1 & J2) are wall outlets so I can plug in
> other things (like a rotary spark gap).
> 
> I did not include filter caps as you mentioned because I don't have any with a
> high enough voltage rating.  If you think it is necessary for the protection of
> the main transformers, I will get them.  My past experience (with a lower power
> system) has been that big enough inductors and a nice safety gap seems to work
> pretty well.  What do you think?
> 
>          -Dan

True enough that big inductors are good enough.  The problem is that as you increase
your power input, the inductive value must get large.  Also, with more power in, you
get more RF back.  So, in order to keep the RF out of the transformer, you really
need the filter capacitors.  Your exact capacitor and inductor values will depend
upon voltage and current levels available.  In general a 5 mH ferrite core choke and
a 1000 pF capacitance value per leg will work to remove 90% of the RF, if you are
running in the 100-300 KHz range.  Don't use air core chokes, they won't give you
the performance you need.

It is also very important that you have that safety gap with a center RF ground reference.
This will keep the resonant voltage rise from getting to the transformer.

Scott Myers