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Re: Guide 60HzMatch

Tesla List wrote:
> 
> > > Subject: Guide 60HzMatch
> 
> Subscriber: Rodney.Davies-at-anu.edu.au Fri Jan 31 22:57:26 1997
> Date: Fri, 31 Jan 1997 20:41:52 +1100 (EST)
> From: Rodney Graham Davies <Rodney.Davies-at-anu.edu.au>
> To: tesla-at-pupman-dot-com
> Subject: Re: Guide 60HzMatch
> 
> Hi,
> 
> On Thu, 30 Jan 1997, Tesla List wrote:
> 
> > > Subject: Guide 60HzMatch
> >
> > Tesla List wrote:
> > >
> > > All,
> > > I need feedback on the following possible entry for the Guide. (It is no
> > > longer the Idiot's Guide. Just the Guide).
> > >
> > > *** Beginning of article
> > > MATCHING THE IMPEDANCE OF THE TRANSFORMER AND THE CAPACITOR
> 
> There's a formula that I use to match capacitors with transformers (and
> vice-versa) which I read in an article from a scientific magazine several
> years ago. The hobbyist was using neon centre-tapped transformers of
> around 300-400VA.
> 
> I myself have found this formula to be relatively accurate and has
> actually worked out for other high-power transformers (ie pig-poles).
> 
> C =  1 / (2*Pi*F*R)
> 
> Where F = 50/60Hz
>       R = transformer impedance (V/I)
>       C = capacitor value in Farads.
> 
> So, if we have a 15KV -at- 30mA neon centre tapped xformer on 50Hz,
> 
> V/I = 15000/0.030 = 500000 Ohms
> 
> C = 1 / (2*3.141592654*50*500000)
>   = 0.000000006 Farads
>   = 0.006 microfarads
> 
> I also applied this to a known commercial Tesla Coil which was 20Kv -at- 12.5KVA
> (Bill Wysock's Super Model 9), and applying the formula -
> 
> This Power supply is running from a 240volt 50Amp power point at 50Hz.
> 
> V = 20000 volts
> I = 0.625 Amps
> V/I = 32000 Ohms (R)
> F = 50 Hz
> 
> C = 1 / (2*Pi*50*32000)
>   = 0.099 microfarads.
> 
> Having already seen this coil close-up myself, there are two 0.05
> microfarad capacitors in paralell to give 0.1 microfarads.
> 
> I'm not certain exactly what type of transformer it is, but I think
> either a single wire earth return or pig pole.
> But I do know for certain it's not neons! :-)
> 
> But as you can see, the figures are pretty damn close!
> I rely on this formula and it hasn't failed me yet!
> 
> Hope this can help some people, it certainly has helped me.
> Also, be rearranging this formula, you can determine what type of voltage
> & current you require to drive some capacitors if you know their values.
> 
> Catchya later!
> 
> Happy Coiling.
> 
> Rod


Rod -

  I have actually helped Bill set up model 9 ...

  Bill has a rather interesting assortment of pigs, and if memory
serves, has run it from several different pigs. Interestingly, the
primary is of very few (under 5) turns.

  The synchronous rotary gap on it is a thing of beauty as well.

- Brent