RE: Calculation of PFC Capacitors using LTR Capacitor

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

Original poster: "John H. Couture by way of Terry Fritz <twftesla-at-qwest-dot-net>" <couturejh-at-mgte-dot-com>


Ed -

The PFC caps are sometimes a nescessity if several LPF NSTs are used in
parallel. For example from the France catalog three 15 KV, 60 ma LPF NSTs
would draw at full load 7.8 x 3 = 23.4 amps and require a 30 amp circuit.
Three HPF NSTs would draw  4.4 x 3 = 13.2 amps and could use a 20 amp
circuit.

The LPF NSTs each draw 890 VA at full load and the HPF draws 495 VA. I
estimate you would need about 100 uf for each LPF NST to bring them up to
the HPF 495 VA input level. You would then be able to use the three LPF NSTs
on a 20 amp circuit. Using the LPF and PFC caps would normally be cheaper
than using the HPF NSTs which cost more than the LPF. The alternative is to
install a new 30 amp circuit. In fact the HPF NSTs would have 100 uf caps(?)
installed internally to bring them up to the HPF level.

John Couture

-----------------------------------

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Saturday, August 03, 2002 12:00 PM
To: tesla-at-pupman-dot-com
Subject: Re: Calculation of PFC Capacitors using LTR Capacitor


Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<evp-at-pacbell-dot-net>


	Agree.  The capacitor will indeed reduce the no-load line current.
Still question whether it is worth the bother.

>

	I agree with that last sentence completely, and also with the philosphy
of the paragraph.  The reason I wrote the questions is that I get the
impression from what I read here that a lot of fellows think that a PFC
is a necessity.

Ed