Re: RE- Cap Confusion

To: "'Tesla List'" <tesla-at-poodle.pupman-dot-com>
Subject: Re: RE- Cap Confusion
From: Tesla List <tesla-at-stic-dot-net>
Date: Mon, 17 Nov 1997 23:47:49 -0600
Approved: tesla-at-stic-dot-net

From: 	mikey1[SMTP:mikey1-at-gladstone.uoregon.edu]
Sent: 	Monday, November 17, 1997 11:38 AM
To: 	Tesla List
Subject: 	Re: RE-  Cap Confusion

Tesla List wrote:
> 
> From:   Robert Michaels[SMTP:robert.michaels-at-online.sme-dot-org]
> Sent:   Sunday, November 16, 1997 6:26 AM
> To:     tesla-at-pupman-dot-com
> Subject:        RE-  Cap Confusion
> 
>         The use of power-factor correcting a capacitor is of very
>         limited usefulness in a single-phase circuit.

    [SNIP of pfc's in three phase, esp. delta configuration]

>         In the case of a lone experimenter and a single-phase load,
>         they are hardly worth discussing.

I no doubt agree with your conclusion in regards to the cost/benefit
analysis of power factor correction capacitance on single phase lines,
after all, the Watt/hour meter outside will still charge you even when
you can cancel out the inductive I shift with a capacative I shift. 
Even though you see no I drawn on your meter, go outside and look at the
spinner whirl.

However, I have found that using pfc's in || to my neon primary (where
else?!?!) reduces the growling effect which seems to eminate from both
the variac and the neon if no pfc's are used.  Just generally makes
things smoother, at least for me.

I am curious as to whether or not those who are using distribution Xfmrs
go with pfc's. 

p.s.  I derived a different formula for pfc size based on completely
cancelling out the inductive current lag.
      It is of the form:

      pfc = var / (2*pi*f*V^2)

      where pfc is in Farads, var is the desired reactive Volt-Amps
(Xfmr VA rating), f is the frequency
      of the applied voltage, and V is, well, voltage.	

Mike Rusher.

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