RE: 5MV, 15/120mA Tesla Coil

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

Original poster: "John H. Couture" <couturejh-at-mgte-dot-com> 


Bart -

I believe you have my TC Construction Guide. Look on page 14-12 for a
description of the 5MV coil and on page 5-5 for a short description of the
operation.

This TC was immerged in a large tank of oil which made high voltages
possible. It produced 1700 KW with an input of 3 KW a gain of over 500 with
an energy transfer efficiency from primary to secondary circuits of about
25%.

John Couture

-----------------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Sunday, January 04, 2004 9:06 PM
To: tesla-at-pupman-dot-com
Subject: Re: 5MV, 15/120mA Tesla Coil


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.
 >
 >
 >
 >