Re: What size PFC should i use with my 15/30 NST?

["Barton B. Anderson" <tesla123-at-pacbell-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi John M., Terry, 

Tesla list wrote: 
>
> Original poster: Terry Fritz <twftesla-at-uswest-dot-net> 
>
> At 10:50 PM 8/29/00 -0500, you wrote: 
> > 
> >Hi again, 
> > 
> >I do have another question.  I would like to put a PFC on my NST but don't 
> >know what size cap to use.  It is a 15/30 stock NST.  I'm using a 13nf MMC 
> >with a 120 bps SRGS (if that makes any differenc).  Any recomendations out 
> >there?  If so, is there a formula or rule of thumb to use to determine what 
> >size PFC to use? 
> > 
> >Thanks in advance, 
> >John M. 
> > 
>
> I think this is correct.  It was posted awhile back and needed about three 
> typo corrections but this should be right. 
>
> Cpfc = ( Vo x Io ) / ( 2 x pi x f x Vi^2 )


This is correct. I posted a few days ago as Cpfc(uF) = (KVA *
10^9)/(2*pi*f*Vi^2). 
That was wrong. The 10^9 should be 10^6. Anyway, the value is uF. PFC's due to
their size are typically rated in uF. 

Just wanted to correct my previous blunder. 

Bart 
>
>   
>  Where 
>         Cpfc = Power factor cap value in Farads 
>         Vo = Rated NST output voltage in volts 
>         Io = Rated NST output current in amps 
>         pi = 3.14159... 
>         f = AC line frequency (50 or 60Hz) 
>         Vi = AC input voltage (120 VAC) 
>
> Cheers, 
>
>         Terry