Re: pole pig current limiting

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

Original poster: "Gregory Hunter by way of Terry Fritz <teslalist-at-qwest-dot-net>" <ghunter31014-at-yahoo-dot-com>

I use a "BuzzBox" brand AC stick welder to ballast my
5KVA pole transformer. I advertised in my local
classifieds asking for a broken arc welder and
offering free pickup. My idea was to salvage the
transformer from a dead welder and rewind the core for
a pole pig ballast. A neighbor replied to the ad and
said he had an old welder in his shop that had never
worked properly. He sold it to me for $25. I took it
apart, cleaned it up, painted the jacket, and put it
back together. It seems to work fine--I even used it
to repair the deck of my riding mower! It is also a
very efficient 240vac ballast. With the welding leads
open, It provides about 8A to my xfmr. This is just
right for tune up and most demonstration purposes.
With the welding leads shorted together and current
turned down to minimum, the current draw jumps to
about 28A. This is pretty intense inside my garage--I
only have 8' ceiling! Maximum possible current is 48A,
but I rarely use this much power--it's just plain
scary to run this much juice to my little coil in my
little garage.

http://hot-streamer-dot-com/greg/buzbox.htm

Before I bought the arc welder, I used two MOTs in
series with their secondaries shorted out. The MOT
twins drew about 20A and made a very compact ballast.
The MOTs tended to run pretty hot, so I kept them in a
steel ammo can filled with motor oil.

Just a thought--if one 500' spool of #12 will regulate
120vac, then two such spools should regulate 240vac.
Just put one spool in each leg of the 240vac. If 25A
is more current than you want or need, then place a
fat bundle of soft steel wires inside the spools. The
added inductance should reduce the current.

Best Regards,

--- Tesla list <tesla-at-pupman-dot-com> wrote:
 > Original poster: "Rodney Goolsby by way of Terry
 > Fritz <teslalist-at-qwest-dot-net>" <jeronimo-at-bright-dot-net>
 >
 > I understand how to make a "Pore Man's Ballast" (500
 > ft spool of 12AWG from
 > home depot) and run it in series with the "Hot" line
 > on a 120 volt input
 > for a potential transformer.
 > They are suposed to let between 25 and 30 amps pass
 > through.  What should
 > you do to make something almost as cheap and almost
 > as easily for, say a 5
 > KVA pole pig with 240 volt input?
 >
 >


=====
Gregory R. Hunter

http://hot-streamer-dot-com/greg