Re: Tesla Coil toroid Size

To: tesla-at-pupman-dot-com
Subject: Re: Tesla Coil toroid Size
From: Greg Leyh <lod-at-pacbell-dot-net> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Mon, 21 Sep 1998 06:28:16 -0600
Approved: terryf-at-verinet-dot-com

> Original Poster: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
>
>   It has taken me some time to digest what you have said in your post. You
> said "this equation is totally wrong". Are you referring to the equation or
> just to the units? The equation units should be -
>
> (watt seconds) x (breaks/seconds) x (1/eff) = watt breaks/eff
>
>   You say the equation is wrong but give no explanation. Could you clarify
> your statement?


In response to your post:
> >>   In my TC Construction Guide I show the following equation (modified) -
> >>   watts seconds = .5 x Cp x Vp^2 x BKS/EFF
I explained:
> >I'm sorry, but this equation is totally wrong.  The quantity
> >(0.5 x Cp x Vp^2 x BKS/EFF) has the units of watts, not watt-seconds.
> >The rest of your derivations that follow from this equation
> >will therefore require correction.

The quantity 0.5xCpxVp^2 is Energy, namely the energy in the primary
cap.
Energy is measured in Joules.
The quantity(0.5xCpxVp^2) * BKS is Power, since BKS is the number of
times
per second that the cap dumps its energy.  Power is the amount of energy 
delivered per unit time.  Power is measured in watts, which is one
Joule/sec.
The quantity(0.5xCpxVp^2) * BKS/EFF is also Power, since EFF is
unitless,
and just describes how much of the power was lost.
Now "watt-seconds" describes a quantity of energy, that is the total
energy 
delivered by a watt in one second.  Therefore it is incorrect to say:

 watts seconds = .5 x Cp x Vp^2 x BKS/EFF

because the equations' units state that 'energy = power', which is not
correct.
Any derivations that follow from this equation will share the same
problem.
-- 


-GL
www.lod-dot-org