Re: Desktop Bipolar Coil

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

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

In a message dated 7/1/03 8:15:44 PM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:


>Watt seconds,(energy) is  being discussed because the TC input energy is
>required if Tesla coil efficiency is to be used to compared them.


John,

Your goal is determine TC efficiency, and mine is to determine what
input power is needed for a certain maximum spark length.  At least
that's what I intended my formula to be used for.  I don't think any
folks think that my formula has anything to do with true efficiency in
the sense of power is vs. power out.


>The Tesla coil efficiency =  energy out/energy in.
>The energy out and energy in are the true energies for a particular random
>spark. These energies are not easy to determine.


Generally the goal of a coiler is long sparks.  It's possible for a coil
to more efficient in the true sense of coil effiency, yet give shorter sparks.
For example, one may have a coil that uses 1kW and gives a
30" controlled spark length, and a 42" maximum spark length.
Another coil may use 1kW and give 33" controlled spark length,
but give only 40" maximum spark length.  Most folks would rather
have the coil that gives longer max sparks, even though it's less efficient
in the true sense.  These kinds of situations may possibly occur due
to certain toroid sizes, breakrates, or other factors.


>Single sparks are not being considered here as coilers seldom use this
>method of comparing Tesla coils. Single sparks present a different problem
>compared to multiple sparks. When multiple sparks are used the problem is
>trying to find how much of the input TC watt seconds belongs to that special
>extra long random spark. It does not appear that this will be possible until
>new methods of instrumentation are devised.


Well, since sparks grow in the air from break to break in a
random way, what you propose may not be desireable.


>Finding an average length spark over a certain period of time would be
>useful if it was possible. However, I do not believe any coiler has ever
>made or could make these measurements.


Some sort of average length may be determinable by using a video
camera


>Random sparks can be turned into constant length sparks by using the
>controlled spark method. The output then becomes a constant energy output
>that can give a coiler an overall efficiency for his coil that makes sense.
>This appears to be the only option for the coiler at present.


How do you know that the controlled output spark length truly
represents the energy in the spark?  I believe it does not.  One could
have short sparks with high energy in the spark, and one could also
have long sparks with low energy in the spark.  This may depend
of toroid sizes, breakrates, and other factors perhaps.

John


>John Couture