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RE: Induction heating in toroid / short circuit of secondary

Hi Ken & All,
Merry Christmas.
Just departed the TRW electronics/radio swapmeet, a few hundred showed.

When the toroid is acting as an open turn its current is minimal
producing no EM field, especially w/no breakout
    but it still influences field control (tames arcing) 

    The fact that an arc can be drawn between the open ends
    of a single fat turn suggests presence of a substantial EM field !

  With break out there is moderate peak current producing moderate EM field
    but produces unchanged field influence (same as open)

When toroid is shorted turn I do expect an EM field proportional
 to current in the shorted turn toroid.

When toroid is open EM field producing current source is the Spark load or 
 perhaps its the toroid charge current being max at time zero. (?)

>If you mean by ES, electro-static field, I don't think there is one:
>"static", after all, means "standing still".  That is, a bunch of
>electrons just sitting there.  Not so, in a t.c.  

You deny the existence of a dynamic ES field around the toroid (and Sec) ???

Maybe I'm confused, won't be 1st time :)  (terminology ?). 
I view the electric field (voltage) as an electrostatic field.
  ( which as you point out is at "rest" 
    so dynamic or changing ES field may be meaningless ?)
in contrast to electromagnetic (current) 
Is this faulty ? (where's Malcom when I need him ? :)

Is there not a dynamic ES Electrostatic Field around the topload toroid 
being one of two electrodes of a HV Capacitor ???

I've always believed the Csec ES energy store was the 1st order provider for
Sparks.
My instrumented TC shows 20-28" power arcs last only ~<400nS 
so too fast to get much energy dump from the inductor.

I believe the EM field from the inductor provides the 
source of energy (-at-~200kHz)converted to charge the ES field of 
 Csec (mostly Ctop) (~3 cycles resonant rise)
 which provides a HV, low impedance source for the
 high peak current, high frequency (Mhz) arc. 

Fellow list physicists: Re: dynamics of an ES field:
Is there a limit to the rate one can produce/remove or reverse and ES field
?

Either/both intense ES (just E?) or EM fields radiate enough energy 
to energize ions or phosphors to light florescent lights at great distance.
Van de Graf, etc. !

Regards, Dale

-----Original Message-----
From: Tesla List [mailto:tesla-at-pupman-dot-com]
Sent: Friday, December 24, 1999 5:36 PM
To: tesla-at-pupman-dot-com
Subject: Re: Induction heating in toroid / short circuit of secondary

Original Poster: Kennan C Herrick <kcha1-at-juno-dot-com> 

Dale-

I'll intersperse a few comments.

On Thu, 23 Dec 1999 12:15:18 -0700 Tesla List <tesla-at-pupman-dot-com> writes:
>Original Poster: Dale Hall <Dale.Hall-at-trw-dot-com> 
>
>1.) In pointing out open Vs closed toroids:
>  Behavior, i.e. max point to point power arc achievable, 
>  corona, spurious Sec arcing, etc.
>  remained Unchanged !
>
>Your comment infers it is the EM field that is responsible.
>
>So why is there no change when I Open the toroid ? (& vice versa?)
>  I keep the open end distance great enough such there is No arcing.
>    (except when specifically testing for sparks between the open 
>ends)
>    (so there is no shorted turn via arc conduction in the major 
>axis)
>  The toroid is just a large ROC top secondary turn,
>  aiding or opposing, with no discernable difference in TC 
>performance;
>
>or could the minor 8" dia shorted portion create an EM field ?
>
As I say, I think it likely that either 1) the secondary's EM field, at
the top, is fairly weak or 2) a good part of that field, repelled by the
self-generated field of the shorted turn, merely passes around between
the top of the coil and the toroid instead of passing through the toroid.
 In either case, the secondary's total field is negligibly changed.
 
>  Thats why I question EM Vs ES field influence. 
>
>  From my tests, I would conclude the whole effect is ES.
>  Same max ppArc, same corona inhibition, eliminates turn to turn 
>arcs, etc.
>  The shorted turn EM fails to alter any operating characteristic,
>perceivable.
>
If you mean by ES, electro-static field, I don't think there is one:
"static", after all, means "standing still".  That is, a bunch of
electrons just sitting there.  Not so, in a t.c.  But I'm sure you mean
the more general <electric field<, in which case, I don't see how such a
field (from the toroid, presumably) is going to affect the secondary
much.  (But the electric field--I assume from the secondary--surely
affects the fluorescent lights in my workshop: those 8' tubes blink
brightly with every "bang".)

>2.) I use the largest possible toroid to intentionally 
>    inhibit spontaneous breakout, permitting my control
>    to place a projection of sufficient length and ideally 
>    cone shaped to a sharp point for field concentration,
>    encouraging maximum charge accumulation & concentration per bang
>    in the topload Capacitance before unleashing its stored energy as
>    as a singular optimal power discharge 
>    possessing maximum length & brightness (pk current) 
>
Well put!  

>    Selection of a smaller ROC to optimize multiple breakout
>    is the more typical coiler objective. 
>
>3.) While R in a toroid shorted turn may be very low,
>    in the presence of an intense EM field
>    Current is verrrry high (kA's) then so it the power
>       unless as proposed the toroids EM field is able to squash
>       down the opposing field without wasting significant energy. 
>         which is hard to accept (no free lunch)
>
That verrrry high current will, of course, produce a verrrry high
counter-magnetic field.

>    That's why I checked for arc production between the open ends, 
>    to check for significant induction.
>    Ends arced, so it appears there is !
>         or can you present another mechanism responsible ?
>
That might offer a handy way to check for t.c. power output:  Just insert
a meter there!  Or better still--try connecting a meter across the
diameter of the toroid, measuring the voltage there.  Or maybe a few LEDs
or even a little battery-operated LCD panel meter suitably rectified.
Endless possibilities!

>-----Original Message-----
>From: Tesla List [mailto:tesla-at-pupman-dot-com]
>Sent: Wednesday, December 22, 1999 4:44 PM
>To: tesla-at-pupman-dot-com
>Subject: Re: Induction heating in toroid / short circuit of secondary