inductive ballasting

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

Original poster: "Mr Gregory Peters by way of Terry Fritz <twftesla-at-qwest-dot-net>" <s371034-at-student.uq.edu.au>

Hey everyone,

I am looking for a cheap heavy duty welder to ballast my pig. I 
currently only have a 140A welder in my garage. I was wondering if this 
would be sufficient for low power testing? I am worried that it is too 
small and the core will saturate - causing effectively no ballasting at 
all. Any advice would be great. I have read stories in the archives 
about difficulties encountered when using purely inductive ballast at 
high power levels, such as difficult to control variacs, etc. Is this a 
really big problem? How exactly does one combat this with resistive 
current limiting? 

If I was to use the 75kVA pig, I don't want the worst case scenario, 
whereby the variac swings to full power, the welder can't ballast the 
pig, the high current surge fuses the circuit breaker and the whole 
house explodes, along with all the pole pigs within a few blocks :) :). 
I would like some sound advice on this subject. Exactly how strong is 
the force created on the variac?
Cheers,

Greg Peters
Department of Earth Sciences,
University of Queensland, Australia
Phone: 0402 841 677
http://www.geocities-dot-com/gregjpeters