Power factor correction yes, but where?

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

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Mddeming-at-aol-dot-com>

Hi All, 
        I don't think this has been asked recently. If the purpose of the 
PFC cap is to make the load on the lines look resistive rather than 
inductive, and your have a Variac across the line upstream of an 
NST/OBIT/MOT/ etc., isn't the power source "seeing" the inductive lag caused 
by the Variac rather than that caused by the Xfmr?  If so, should the 
correction be made at the Variac rather than at the Xfmr, or would both be 
recommended?  I don't think I've ever seen the correction equations for 
sizing a cap to a Variac. I have 55 15uf -at- 660 V run caps to play with, if I 
need to use a bunch. 

Thanks, 
Matt D.