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Re: Guide 60HzMatch
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> From: Tesla List <tesla-at-poodle.pupman-dot-com>
> To: Tesla-list-subscribers-at-poodle.pupman-dot-com
> Subject: Re: Guide 60HzMatch
> Date: Saturday, February 01, 1997 1:15 AM
>
> > > Subject: Re: Guide 60HzMatch
> > > Subject: Re: Guide 60HzMatch
> > Subject: Re: Guide 60HzMatch
> > > Subject: Re: Guide 60HzMatch
>
> Subscriber: bert.hickman-at-aquila-dot-com Fri Jan 31 22:54:52 1997
> Date: Fri, 31 Jan 1997 07:01:59 -0800
> From: Bert Hickman <bert.hickman-at-aquila-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Guide 60HzMatch
>
> Tesla List wrote:
> >
> > > Subject: Re: Guide 60HzMatch
> > > Subject: Re: Guide 60HzMatch
> >
> > Subscriber: tom_mcgahee-at-sigmais-dot-com Thu Jan 30 23:04:43 1997
> > Date: Thu, 30 Jan 1997 22:43:20 -0500
> > From: Thomas McGahee <tom_mcgahee-at-sigmais-dot-com>
> > To: tesla-at-pupman-dot-com
> > Subject: Re: Guide 60HzMatch
> >
> > [The following text is in the "ISO-8859-1" character set]
> > [Your display is set for the "US-ASCII" character set]
> > [Some characters may be displayed incorrectly]
> >
> > ----------
> > > From: Tesla List <tesla-at-poodle.pupman-dot-com>
> > > To: Tesla-list-subscribers-at-poodle.pupman-dot-com
> > > Subject: Re: Guide 60HzMatch
> > > Date: Wednesday, January 29, 1997 11:10 PM
> > >
> > > Subscriber: Esondrmn-at-aol-dot-com Wed Jan 29 21:02:07 1997
> > > Date: Wed, 29 Jan 1997 15:25:54 -0500 (EST)
> > > From: Esondrmn-at-aol-dot-com
> > > To: tesla-at-pupman-dot-com
> <BIG Snippola>
>
> > >
> > > Fr. McGahee,
> > >
> > > I have two thoughts on the subject. One is maybe we should mention
the
> > use
> > > of Power Factor Correction caps to be used with neon sign
transformers to
> > > reduce the input current requirements and thus the size of the variac
> > needed.
> > > I would imagine most Tesla coils do use neon transformer power due
to
> > their
> > > cost and availability.
> > >
> >
> > Ed,
> > (I got your coil revision and have updated the original file)
> > Yes, Power Correction Caps are important, and should be included. I
found a
> > little on this by Richard Quick. What I'll need to know from the list
> > members is what values to use for the most popular neons (9K 12K 15K
at 30
> > 60 90 ma). I don't have any data on the values yet. I hope someone
reads
> > this and lends a hand! I don't know whether there is a formula people
are
> > following, or just word of mouth.
>
> Ask and ye shall receive! :^)
>
> A rule of thumb that can be used for neons is that they will require
> power factor correction for about half of their faceplate Volt-Ampere
> (VA) rating. For example, a 15 KV 60 MA neon will be rated at
> 15000*0.060 = 900 VA. About half of this (450 VA) "looks" purely
> inductive to the incoming line, and it's this reacitve component that we
> want to "counteract" by using power factor correction (PFC) capacitance.
>
> BTW, PFC capacitors must be AC-rated and non-electrolytic - oil-filled
> mylar "can" type are ideal, and they should be connected directly across
> the line input to the neon(s). PFC's will reduce the amount of current
> drawn from the mains by getting the incoming voltage and current more in
> phase with each other. While this won't save you on the electric bill,
> or make longer sparks, it MAY let you run at higher power levels before
> tripping the branch circuit-breaker in your garage or basement.
>
> The capacitive reactance at a given frequency is 1/(2*Pi*F*C). Knowing
> this, we can solve for the amount of capacitance required to counteract
> the inductive reactance we've got:
>
> Cpfc = (0.5*Vout*Iout*1e6)/(2*Pi*F*Vin^2) in uF
>
> where Vout = faceplate HV output voltage of the neons
> Iout = combined faceplate current of all neons
> Pi = 3.14159
> F = Line Frequency (50 or 60 Hz)
> Vin = Mains voltage (typically 120 or 240V)
>
> Typical values for 120 Volt input neons at 60 Hz are:
>
> 30 60 90 120
> 9000 25 50 75 100 uF
> 12000 33 67 100 133 uF
> 15000 41 83 124 166 uF
>
> BTW, these do NOT need to be exact values to be effective.
>
> <SNIP>
>
> > Fr. Tom McGahee
>
> Safe coilin' to you!
>
> -- Bert --
Bert,
Thanks! I had made some preliminary notes on PFC, and was just about to dig
out some of the old textbooks when I got your input on the Tesla list. This
type of data is needed by almost everybody, and it is a shame we all have
to scrounge around wasting valuable time looking for little items like
these. Hopefully the Guide will give us a repository for just such stuff, a
quick place to go and look for answers to all those FAQ's.
I look forward to hearing from you again! And by the way, please let me
know if you think of anything that needs to be in the Guide that it looks
like I have missed.
Fr. Tom McGahee