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Re: Power factor correction
Original poster: Skip Malley <skip@xxxxxxxxxxxxxxx>
Am I missing something?
An ideal transformer for a modest Jacob's ladder is an oil burner 
transformer of the 10KV / 30mA type.  To do a Jacob's ladder thing, 
that is the best XFMR to use.  For that, there also is no need for 
ballasting.  An oil burner transformer is designed to produce a 
continuous spark.
Any Jacob's ladder that I have made draws about 3 amps from the 120V 
AC line with NO ballasting using an oil burner transformer.
An X-Ray transformer is the wrong transformer for your application.
Skip
At 07:26 PM 6/19/2006, you wrote:
Original poster: "Mike" <mike.marcum@xxxxxxxxxxxx>
I was making a Jacob's ladder with a dialed-down/ballasted x-ray 
transformer (83v 41A in atm, limited by the 30A breaker and dry atm 
'till I build a tank and vacuum it, ebay special so was shipped ups 
dry to save shipping). Close to 38kV and 90 mA out (making a 
mean-looking 12" arc). I wanted to power factor correct this so I 
can pull more current without popping the breaker (or frying my 20A 
variac). What I don't know is what the starting pf is without 
measuring it (good pf DMM's I've seen are $250+). Most nst's use .5 
as a rule of thumb for correcting those. Could this setup be 
considered as a big nst? If so I think I need 1526uF that won't 
change as the current/voltage go up as long as the ballast stays the 
same (unless I goofed on the math somewhere).
PS - The ballast is 2 E cores from old C & H sales 4500v 
transformers with about 5 lbs 10awg and 2" spacers (draws like 8A at 
83V with no gap) between them if that makes a difference.
Mike