Re: Looking for run caps, urgent

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

Original poster: "Rick Williams by way of Terry Fritz <twftesla-at-qwest-dot-net>" <richardwwilliams-at-earthlink-dot-net>

Hi all,

Thinking about this PFC thing. Right now I have 3 15/30s (450 each) in
parallel with a Staco 25amp variac. I will be adding 2 15/60s (900 each) to
the bank. Therefore my curiousity.

I took some measurements with a 0.1ohm 100w resistor in series from the main
AC power. Also a 1K 100w across the output of the NSTs.
Don't know if that's the setup to use but anyway...
current lagged voltage by 3.8 ms with or without the NST load resistor and
no matter the variac setting.

Can the PFC cap be calculated from this? My math is way passed the rusty
stage. :)

Rick Williams
Salt Lake City




----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, October 24, 2001 8:20 AM
Subject: RE: Looking for run caps, urgent


> Original poster: "Ted Rosenberg by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <Ted.Rosenberg-at-radioshack-dot-com>
>
> Thanks Terry. Your formula is the one I used that gave me 165µF.
> I suppose I will do some checking as I go.
> John Morawa was kind enough to provide me with five 34µF suplus Aerovoxs.
> I'll start with 3 then add a 4th etc and take CLampmeter readings.
> But I gotta wait until Nov 1 <sniff>.
> Meanwhile I am gathering info on sound deadening material. I don't expect
a
> "silencer" effect. Just a hoped for reduction in that noisemaker.
>
> Regards
>
> Ted
>
>
> -----Original Message-----
> From: Tesla list [mailto:tesla-at-pupman-dot-com]
> Sent: Tuesday, October 23, 2001 8:44 PM
> To: tesla-at-pupman-dot-com
> Subject: RE: Looking for run caps, urgent
>
>
> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
>
> Hi Ted,
>
> "I" have never quite figured out the PFC thing :-))  My big coil needs
> 200uF of PFC caps as predicted by computer models and proven in real life.
> Most of the benefit from PFC caps in my case is from the first 100uF,  The
> next 100uF does not add too greatly to the current reduction (a case of
> diminishing returns).  You don't want too much PFC capacitance so it is
> best to error on the low side.  There are some formula's..., here is mine:
>
> Cpfc = ( Vo x Io ) / ( 2 x pi x f x Vi^2 )
>
> 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)
>
>
> A search of the archives for "Power Factor Correction weirdness" bings up
> much "stuff" ;-))
>
> www.pupman-dot-com
>
> Cheers,
>
> Terry
>
>
>
> At 12:53 PM 10/22/2001 -0500, you wrote:
> >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 enough.
> >
> >Now here's Jonathan with a figure that meshes with my 165, ie 165 * 2
> ><because he's using a 120mA figure>= 330.
> >So, what's the REAL story?????
> >Inquiring minds want to know  :))
> >
> >
> >Safety First
> >Ted
> >
> >-----Original Message-----
> >From: Tesla list [mailto:tesla-at-pupman-dot-com]
> >Sent: Monday, October 22, 2001 12:33 PM
> >To: tesla-at-pupman-dot-com
> >Subject: Re: Looking for run caps, urgent
> >
> >
> >Original poster: "Jonathan Peakall by way of Terry Fritz
> ><twftesla-at-qwest-dot-net>" <jpeakall-at-mcn-dot-org>
> >
> >Frank and other whow wondered,
> >
> >I need 332uf because I have a 15/120 NST, and that's what the java TC
> >designer prog. says I need. I sure hope that's right, as it looks like
> >getting these caps is gonna be spendy.
> >
> >Jonathan Peakall
> >----- Original Message -----
> >From: Tesla list <tesla-at-pupman-dot-com>
> >To: <tesla-at-pupman-dot-com>
> >Sent: Monday, October 22, 2001 12:07 AM
> >Subject: Re: Looking for run caps, urgent
> >
> >
> >> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> ><PsychoticMinds1-at-aol-dot-com>
> >>
> >>
> >>
> >>         What do u need such a high uf of run caps for?
> >>
> >>
> >>
> >> Frank
> >>
> >>
> >>
> >
> >
>
>
>