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Re: Looking for run caps, urgent



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

There is indeed something amiss.  I extracted this from John Couture's site: 

The following can be used to correct any LPF NST to about 90% power factor. 
C = K1*V*A      
C = PFC capacitor in microfarads(UF)V = NST secondary volts 
A = NST secondary amperes 
K1 = .08 for 120 volts at 60 HZ 
K1 = .02 for 240 volts at 60 HZ 
Example NST 15000 volts 60 milliamps(ma) 60 Hz     
For 120 volts  C = .08*15000*.06 = 72 uf 
For 240 volts  C = .02*15000*.06 = 18 uf 
Do not use larger capacities because this could result in leading power factors
which are undesirerable. 

I think there is some serious discrepency for the PFC calculation. 
Mike 


>
> Jonathan: 
> There seems to be some weirdness here. 
>
> Terry...you might want to jump in. 
> I ran the formula using my 15/60 as a model. The answer was 165µF. 
> But in an earlier e-note you suggested that only 100µF would be enoug