Re: Neon unpotting dilemma (high power factor)

To: tesla-at-pupman-dot-com
Subject: Re: Neon unpotting dilemma (high power factor)
From: Lightingcontrols-at-worldnet.att-dot-net (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Tue, 07 Mar 2000 18:48:46 -0700
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

Hi Adam,
comments after snip

> BUT... when I opened the unit, I see that the situation 
is a bit more
> complex.  The primary seems to be tapped, with a PFC 
capacitor across only
> part of the coil.  Could a failed PFC cap have been the 
actual cause of the
> primary short? I'm thinking now that the HV may have 
arc'd to the PFC cap
> (which was near the HV wires) and killed it, 
effectively shorting the
> portion of the primary in parallel with this capacitor.
> 
The primary may not be shorted.
I had a similar problem with a France NST with internal 
PFC. On mine there were actually two "primarys", one was 
for PFC and the other was the main "normal" primary. They 
were both connected together on one AC input, the other 
AC input was connected to the main primary and one side 
of the cap. The second "PFC" primary is in series with 
the cap, that's how they get PFC with a small 1-2 uf 
cap. Just cut off the cap, let the "PFC" primary float. 
If the main "normal" primary didn't short your 
transformer should work fine, at mabey twice the 
current(not 25 amps).

Good luck!
Allen Cart