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*To*: tesla-at-pupman-dot-com*Subject*: RE: What size PFC ...*From*: Terry Fritz <twftesla-at-uswest-dot-net>*Date*: Sat, 02 Sep 2000 14:37:50 -0600*Delivered-To*: fixup-tesla-at-pupman-dot-com-at-fixme*In-Reply-To*: <LOBBKNJDHNJJKPBJECPBMEEICJAA.couturejh-at-worldnet.att-dot-net>*References*: <4.1.20000901170506.00aaccd0-at-pop.dnvr.uswest-dot-net>

Hi John, At 12:42 PM 9/2/00 -0700, you wrote: > >Terry - > >The rearranged equation is still incorrect when used with active volt amps. >The equation is correct only when used with reactive volt amps. To convert >active to reactive amps you need to use complex numbers or trig functions. I >prefer to use trig functions as I show in my post to the Tesla List 7-14-96 >"PFC for Neons". Can it be that long ago? > >Note that using your "close enough" equation will always give you a leading >power factor which is worst that a lagging power factor. It would be >interesting to see what a model by microSim would show. > >To properly meter the TC load you need at least 4 meters, volts, amps, >watts, power factor. The power factor meter is required to tell you if the >load is leading or lagging. A VAR meter would help and save you having to do >the necessary calculations. > >Bart I am glad to hear that you are researching the problem. As Terry >pointed out there may be other issues and your work may shed more light on >the subject. > >John Couture > >------------------------------ > I pulled up your old post: ============================================== PFC for Neons · To: Tesla List · Subject: PFC for Neons · From: "John H. Couture" · Date: Sun, 14 Jul 1996 17:55:23 GMT Uncorrected neon transformers are usually 50% power factor. To correct them for 90% power factor add a capacitor calculated as follows: For 120 volts c uf = .079 V A For 240 volts c uf = .020 V A V = neon secondary volts A = neon secondary amps The factors K1 = sin(arccos(LPF)-sin(arccos(HPF)) K1 = .43 for 50% to 90% power factor For 120 volts K2 = (.43 x 10^6)/(6.283 F V) F = 60 Hz K2 = (.43 x 10^6)/(377 x 120^2) = .079 For 240 volts K2 = .0198 or .02 Example: Neon 15000 volts 60 ma 120 volts 60 Hz C = .079 x 15000 x .06 = 71.1 uf sniped efficiency text... ====================================== So your saying I should have a 71.1 uF cap instead of my present 200uF on my 15/60 coil... Let's look at the RMS current draw of my 15/60 coil with various PFC caps using MicroSim: Cap size AC line current Notes 0uF 11.16 ARMS No PFC cap 71.1uF 9.19 ARMS John's equation 165.8uF 7.75 Arms "Terry's" equation 200uF 7.72 ARMS The "real" best PFC cap size Cheers, Terry

**References**:**RE: What size PFC should i use with my 15/30 NST?***From:*Terry Fritz <twftesla-at-uswest-dot-net>

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