Overvolting pigs?

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

Original poster: FIFTYGUY-at-aol-dot-com 

Folks-

     After recent posts on running small low voltage x-formers backwards, and
trying to power a 480V pig with 240V:
     How much over the nominal voltage ratings will a typical pig withstand?
I.e., if I put 240V into 120V taps how long will it put out twice the high
voltage rating?
     Seems a lot of folks variac the 14.4kV units to about 18kV out - any
guesses how long it would withstand 28.8kV out?
     While we're at it:
     What, if anything, should be hooked up to the neutral tap of the LV side
of the pig? Any theories as to balancing, filtering, etc., or is it better
left unconnected? I feel the fewer house wires headed to HV land the better.
     And speaking of running x-formers backwards and house wiring isolation, I
was thinking of using a NST run backwards to provide 120VAC for the SRSG from
the HV pig output to the primary circuit. So I suppose I should ask how long
a 15kV NST will last with 28.8kV into the secondary...

-Phil LaBudde