Re: TC efficiency, was Math help...

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 7/16/01 9:49:40 AM Eastern Daylight Time, tesla-at-pupman-dot-com 
writes:

> The input power for a foot of spark always is larger for larger coils
>  compared to small coils. This is an indication that larger Tesla coils are
>  less efficient than small coils. 

John,

The first sentence above is correct, the second is not, in my
opinion, because the the second sentence is not a correct 
logical result following from the first sentence.

>  I think Tesla mentioned this in the CS
>  Notes. The reason is that large coils have much heigher voltages than small
>  coils and this increases the corona, etc, losses per unit of output/input.

I often see a lot less corona on a large coil.  In any case, Tesla
made plenty of mistakes, even though he was a genius and a good guy.
>  
>  Note that coupling is not involved with efficiency, only with the
>  Coefficient of Leakage which is an interesting magnetic circuit limitation
>  for Tesla coils.

Coupling is indeed involved with efficiency, but indirectly.  If the
coupling is too low, the energy stays in the primary too long, and
gap and primary losses increase.

>  
>  I agree we have a lot to learn about Tesla coils before we can design them
>  with a minimum of guestimating.

I can a agree with that.

JOhn Freau
--
>  
>  John Couture