Re: Pool Pig...

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: <chipford@xxxxxxxxxxxx>

Thanks Greg. This is comforting. I have a buddy that works in the 
electric utility business. They are the folks that sub-contract 
replacing the end of shelf life poles and stuff like that. He tells 
me he can get me a 10 or 15kva pole pig pretty easy.   He said that 
about all of them are the 7200 volt variety.

 With all of this said, can I just build a say 8 1/2" dia. X 48" 
secondary with about 1200-1400 turn of 20-24awg wire on it and then 
lay down 10-15 turns of copper tube say 24" diameter 1/2" apart, hook 
a couple of .03uf X 30KV maxwell caps in, hook it to my pole pig, do 
some tweaking and create lightning? ;^P

See attached photo...
http://hot-streamer.com/temp/variac-0a.jpg


---- Tesla list <tesla@xxxxxxxxxx> wrote:
> Original poster: G Hunter <dogbrain_39560@xxxxxxxxx>
>
> Hi Chip,
>
> The transformer / cap matching formulas often break
> down when pole pigs are involved for precisely the
> reasons you've just illuminated.  An optimal cap for
> 7200vac at 2 amps is just too big.  It's not a big
> deal.  Smaller-than-resonant caps are the norm at such
> power levels.  Start off with about 50nF and
> incrementally add capacitance until you get decent
> sparks.  Maxwell Labs 30nF 30KV plastic caps go for
> about $100 apiece on e-bay these days.  Try one or two
> of those to start with.
>
> Cheers,
>
> Greg
>
>
> --- Tesla list <tesla@xxxxxxxxxx> wrote:
>
>  > Original poster: "Chip Ford" <chipford@xxxxxxxxxxxx>
>  >
>  > Ok...there are many kinds of transformers out there.
>  > Seems that the
>  > really BIG coils use a pole pig. Such as "The green
>  > monster". His is
>  > a 15kva @ 14400 volts. Using the math KVA = ((VOLTS
>  > X AMPS) / 1000),
>  > I came up with an amperage of @ 1.042 Amps (15,000
>  > watts). Since .001
>  > Amps is equal to 1ma, he has 1042ma. According to my
>  > calculations,
>  > the resonant cap is @ .1919 uf. I think he said his
>  > cap was
>  > .1uf...close but not real close..Now, I think alot
>  > of the line
>  > transformers have a selector switch on them. I think
>  > they are like
>  > 7200, 6400, 5600 volts for the ones around here. So,
>  > if I have 15 kva
>  > transformer @ 7200 volts, it will have an amperage
>  > of @ 2 amps
>  > (2000ma)(15,000 Watts). At this rate, my cap is
>  > gonna be around .75
>  > uf. This is really high and from a few calculations
>  > that I have made,
>  > A secondary coil 12" 81/2" dia. 48" tall will need
>  > over 10000 turns
>  > of #39 awg. wire on it. This pretty much makes this
>  > transformer
>  > unusable. Besides that, where is a hobbest ever
>  > gonna find a cap? Am
>  > I missing something here? Are my calculations
>  > incorrect? Am I looking
>  > at the transformer incorrectly? Please
>  > comment...Chip Ford
>  >
>  >
>  >
>
>