Re: Potential Transformer Sources

To: tesla-at-pupman-dot-com
Subject: Re: Potential Transformer Sources
From: "Ed Phillips" <evp-at-pacbell-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Sat, 15 Apr 2000 10:59:07 -0600
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

Tesla List wrote:
> 
> Original Poster: "Herwig Roscher" <herwig.roscher-at-gmx.de>
> 
> Max Erhard wrote:
> 
> > What kind of MOT's are potted in resin, I haven't seen any ?
> 
> Max,
> 
> Maybe "potted" is the wrong word. Sorry.
> 
> The MOT's immersed in a kind of hot, clear varnish/resin. After the
> air is pumped out, the varnish fills all of the space between the
> turns and between the windings and the core. After removal of the
> MOT the varnish hardens. Therefore oil wouldn't provide any
> additional insulation.
> 
> How do you call this process which is indeed very similar to the
> treatment of rolled/horizontally stacked polycaps?
> 
> Bye             Herwig

	In my experience the process is called "vacuum impregnation".  It's
most important benefit, if it's done properly, is to exclude air from
the inter-winding space, eliminating failures due to corona and
insulation degradation. Very important for capacitors as well as
transformers and inductors.

Ed

Ed