Re: 5MV, 15/120mA Tesla Coil

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

Original poster: Bart Anderson <classi6-at-classictesla-dot-com> 

Does anyone have any specific details on the whole system?
Bart

Tesla list wrote:

>Original poster: dhmccauley-at-spacecatlighting-dot-com
>
>I seriously doubt they were even close to 5MV.  There are problems with this
>that are blatantly obvious.
>
>1.  If this was a classic magnetically coupled tesla coil, that kind of
>voltage could never form on the discharge terminal (topload) of that
>secondary without
>first striking over to the primary at a much lower voltage.
>
>2.  The topload would have to be absolutely huge to allow that kind of
>voltage to build-up.  Small toroids would have a much lower break-out
>voltage and there would be
>a discharge at a much lower voltage that obtainable.
>
>3.  Also, with only 120mA at 15kV, there is not enough power available to
>get 5MV in a single discharge cycle unless you were
>charge pumping a topload capacitor or similar over many cycles.  The gain is
>approximately = 333 which is ENORMOUS!
>Since Gain = SQRT (Cp/Cs) the secondary capacitance (self-capacitance of
>secondary + topload capacitance) would have to be approximately 110,000
>times
>smaller than the primary capacitance!  Considering you new a large topload
>to begin with to allow the voltage to build-up that high, you would have a
>very large
>primary capacitance and a 15kv/120mA transformer would NEVER be able to run
>that.
>
>I may be wrong here, but I think even the largest pole transformer tesla
>coils (>30kW) would have trouble getting to 5MV output!
>
>
>Dan
>
>
> > I read somewhere a few years ago on the TCBA newsletter (I think) about a
> > team of coilers (pro physisicts? can't remember) that made an 8"x40"
> > secondary with ~7000 turns of 42 awg. They managed still to get 5 million
> > volts out of it with if I remember right a 15/120 supply. I take it that
> > higher voltage doesn't necessarily mean longer spark, but am I overlooking
> > something else? I don't think they mentioned the output length, but 5MV is
> > hard to picture short.
> >   What if I keep the primary inductance high and add a bigger topload?
>This
> > was my original idea, but was thinking that adding a breakout point
>reduces
> > the effective capacitance, or does it do the equivelent of making it a big
> > leakier capacitor? Can't test this without my scope and kinda chicken to
>try
> > since it's not a robust tube unit.
>
>
>
>