RE: Warning about Magnetek(sp?) Jefferson NST's and a depotting question.

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Garry Freemyer by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Garry-at-NDFC-dot-com>

Hmm, interesting thought. There might be tracking through the tar to the
core tho. I am going to depot all new NST's after this one because that
Jefferson arching like that no doubt melted several windings and maybe even
for four or so layers. I might tear it apart completely and unwind the
secondaries till I get to an undamaged layer.

I don't know if it is common but it is entirely preventable on thier part.
On all the other NST's I have taken apart, there was always some sort of
insulating shielding between the secondaries and the enclosure to prevent
this kind of thing but whith the Jefferson's there was no shielding at all.
I suspect the tranformer would not have arced if they had attached it to the
center of the case instead of being placed so the tranformer was way off to
one side of the case. On one side, there was only the 8th inch of space
between the windings and the case but on the other side, it was at least an
inch of space there.

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Friday, December 29, 2000 11:10 AM
To: tesla-at-pupman-dot-com
Subject: Re: Warning about Magnetek(sp?) Jefferson NST's and a depotting
question.


Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<FutureT-at-aol-dot-com>

In a message dated 12/29/00 1:41:52 AM Eastern Standard Time, 
tesla-at-pupman-dot-com writes:

> > One of the secondaries of the tranny was arching to the case that was
MUCH
>  > LESS THAN AN EIGHTH OF AN INCH AWAY!!

Garry,

I wonder if this 1/8" spacing is common in the Jeffersons?
If so, One could simply cut away the metal of the case, at four
places on each side of the case, so the secondaries would have
nothing to arc to.  There would be no need to de-pot or open
the transformers, once it is known exactly where to make the
cuts, based on the position of the secondaries, etc.  Of course
if a larger area is cut away than needed, that would be fine too.

John Freau