Re: Defeat the SGFP Transformers!

On Wed, 09 Jun 1999 12:49:09 -0600, you wrote:

>Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
>At 01:46 AM 6/9/99 -0400, you wrote:

>If anyone has info on these let's get it posted and let the fun begin!
>I wonder if a Tesla cap discharged into the relay would help to weld it
>closed :-))  Hopefully, we can figure out the work around before we ever
>see the first one.  Of course, the neon sign guys may do it for use if the
>thing works as poorly as I suspect...  Hopefully, the new gizmos will fail
>often and send large numbers of almost new transformers to Tesla land...  I
>bet the new designs will be dropping like flies.  Just a new bunch of parts
>to fail.  This may be a good thing for us.
>Sounds like a new challenge indeed!  Just what we like :-))
>	Terry

A couple of thoughts - 
Assuming the relay is controlled by some electronics, it may be
practical to zap the control circuitry with a TC - semiconductors tend
to fail short, so hopefully the relay will be held on. Use with a
variac could still be a problem, though, as the relay  wouldn't cut in
below a certain voltage. 
 Epoxy can be dissolved off, but the solvent  would probably take
winding insulation with it. It may be possible to do a partial
immersion to dissolve the epoxy just as far as the relay contacts. 

I wonder however if these requirements will accelerate the move to
'electronic' high-frequency transformers - the higher cost of the
electronics would be partially offset by the protection  circuitry,
which could be implemented more easily on electronic units - now that
would be the _real_ tragedy!