Re: Repost: NST VA Rating and Power Factor

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

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

>  
>  Why such different VA ratings on different 15/60 NST's, and does this
>  have any bearing on whether anything is to be gained by using PFC caps?

Bill,

If a 15/60 is rated at 495VA, then it has pfc caps inside, so it
won't need to have external pfc added.  If the 15/60 is rated at 
960 VA, then it doesn't have pfc inside, and adding external
pfc will reduce the current draw.

>   Also, regarding the problem of tripping the house breaker (It was on a
>   15amp breaker, but there is a 20amp available that I'll try next time):
>   I've got a 240 volt line in my garage (20 amp breaker).  If I use my
>   variac to step this down to 120 volts, will I be able to draw more
>   amperage?  The variac is 240 volt 50 amp, and has multiple terminals,
>   and I think there's a way to use it as a stepdown (other than just
>   leaving the dial at 50%), though I'm not sure how to do this (asking in
>   another post).

Yes, using the variac on 240V will let you obtain 40 amps at 120 volts.
Usually the variacs can step up the voltage but not down, so you
have to just turn it up to 50% max.  

John Freau

>   
>           Thanks,
>           Bill Vanyo
>