RE: Pole transformer ballast

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

Original poster: "Loudner, Godfrey by way of Terry Fritz <twftesla-at-qwest-dot-net>" <gloudner-at-SINTE.EDU>

Hello Steve

Look around for a big arc welder from the old days---the kind that were used
to do very serious welding. I found one at a junkyard for $20. I removed a
transformer that must weight about 250 lbs. The transformer has a
multi-tapped secondary with a 240 volt primary, and it is current limited by
fixed shunts in the core. After mounting the transformer on casters, I have
a big ballast that I can easy move around. It handles my two pigs and two
x-ray transformers with graceful ease. The big old-time welding transformers
can really handle a lot of current through their primaries. Hard to believe,
but the ratings plate says that the transformer can operate at 437 degrees
F. If you find such a transformer for a good price, then you will have extra
money to spend on a tank cap made from MMCs. 

Godfrey Loudner

> -----Original Message-----
> From:	Tesla list [SMTP:tesla-at-pupman-dot-com]
> Sent:	Sunday, July 22, 2001 9:21 PM
> To:	tesla-at-pupman-dot-com
> Subject:	Pole transformer ballast
> 
> Original poster: "Steve White by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <slwhite-at-zeus.ia-dot-net>
> 
> I am thinking of using an arc welder as a pole pig ballast. The cheaper
> welders
> (e.g. Lincoln AC-225)  that I have seen appear to use a multi-tapped
> secondary
> with resistive current limiting on the primary. If so, then I question
> whether
> using one of these would be much better than simple resistive current
> limiting.
> The more expensive welders appear to use a crank mechanism to move the
> primary
> and secondary of the transformer with repsect to each other. This seems
> much
> more desirable as no resistive current limiting is involved. Does anyone
> know
> for certain which welders use the movable transformer core method? I think
> that
> Miller and Century do this but I am not sure. This entire ballasting issue
> is
> proving to be my most perplexing problem.
> 
>