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Update

Well I have finished a rather extensive evening of high-pot
testing and static firing the completely rewired 25kVA pole pig.

I sense many questions, so I will cover familiar ground for many.

A "pole pig" or "pig" for short is a power distribution
transformer of the type utilities hang on poles... Now back to
the update.

First I static tested the rewired pig. This 25 kVA unit has
undergone some significant changes under my irreverent hands.
What was before a mild mannered, quiet, pole pig is now a 2x
overvoltage Tesla power supply. First off... It growls.

This transformer startted out as a commercial grounded core,
single bushing, 120/240 output pole pig with a 7200 volts input.

It is now a two bushing, 14400+ volt output, 0-280 volt input
Tesla power supply. This pig now squeals some.

After I rewired the HV secondary for two bushings it still
behaved very nicely. But when I rewired the dual LV windings
in parallel and pumped 280 volts in for a 16848 V maximum output
it complains some. The core begins to draw current at no load 
when the LV input exceeds about 130-140 volts. At 280 volts input 
the core draws between 4-5 amps static, that is, under no load. I
am sure the lost 1200+ or so watts is going to heat the core and
to produce the growling noise. To be frank, I don't care. The
core is so big, and there is so much oil, that you could heat it
with a torch for hours before it would make a difference. I have
no intention of using this core in continous applications. For my
purposes the excessive losses are acceptable in this application
where high current intermittent use is the norm. The alternative
is spending $$$ to purchase of a pig designed for 14400 volt
application. Since my money was spent years ago on a gamble, I
will own up to the bet for awhile.

With a Jacob's Ladder for a load across the HV bushings the pig
was not as smooth as I had experienced previously. I lost some of
that heavy core resolve when I doubled the voltage. But it did
perform pretty well on the ladder. My wife was concerned about
the growl, and noticed that the arc up the ladder was "snappier"
(inductive surging). All in all it puts out the voltage, but it
does not appear to be nearly as well balanced and smooth in
Jacob's Ladder use.

It will be a couple of more days before I push to fire another
coil in the budding lab. RF shielding and ground work still need
to be completed, be sure that in the next few days you will be
hearing more from me.

Richard Quick


... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12