# Re: power v energy measurements, was Re: SSTC does 10 foot sparks

Original poster: "John Couture" <johncouture-at-bellsouth-dot-net>

Steve -

Your 10.5 inches beats my 8.25 inch record.

You have found the importance of finding the number of sparks in one second
when using this method. How did you measure the sparks?

With this method of comparing Tesla coils you do not have to guess at the
details regarding what is in the Tesla coil or how many volts and joules are
in the capacitors, etc. You are actually finding more accurately the true
energy input of each spark and the performance of that spark to compare with
what
other coils are doing.. This is all that is necessary to compare TC's of any
size or type. Only three numbers from your tests are required.

1. Average Watts input
2.  Number of equal length sparks in one second
3.   Length of those spsrks.

The number of watts and the number of sparks can vary but the calcs have to
be adjusted accordingly. There is much more that can be found regarding your
coil like efficiency, currents, etc. This information would require more
numbers and more tests. However, I believe the above or a better method of
comparing
TC's must be decided upon before we go further.

Do you have any suggestions for improving this method of comparing coils?

John Couture

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

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, June 25, 2004 8:57 AM
Subject: RE: power v energy measurements, was Re: SSTC does 10 foot sparks

> Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com>
>
>  >Before we can go any further this type of test should be
>  >understood and  approved by the majority of coilers.
>
> OK, let me try it.
>
> I can set my OLTC II up such that it uses about 3000 watts and produces an
> arc about 4ft 6ins long. I'm not sure how you would test whether this is
in
> solid contact with the target, but from sound and appearance, it looks
that
> every one of the 600 bangs per second results in a hit.
>
> I can provide proof of this, but I shouldn't need to as 4'6" with 3kW is
> nothing spectacular.
>
> So by John's formula, we have:
>
> 1. Consumption, 3000 joules in one second
> 2. Output, 600 sparks in one second
> 3. Each spark contains 3000/600=5 joules
> 4. Spark is 54" long
> 5. Result, 10.8 inches of spark per joule
>
> My mini OLTC comes in even better- with 300W consumption, 1200 sparks per
> second, and a 9" controlled spark, it gets 36 inches per joule.
>
>  >you will find that the 8.25 inches is a record
>  >that is hard to beat.
>
> Do I get a cookie then?
>
>
>
> The odd thing is, that the performance of my OLTC II is considered to be
> pretty poor, by the standards that most coilers use. It has a "Freau
factor"
> (1 minute sparklength divided by square root of power) of only 1.3 when
> configured for maximum spark length. And the mini OLTC is even worse with
a
> Freau factor of 0.65.
>
> The OLTCs just "cheat" at John's metric because they use a high breakrate
> and relatively low energy, so they achieve their output mostly by streamer
> growth.
>
> ***
> I suggest the following metric, which I think reflects the priorities of
> everyday coilers. To be evaluated over a 2 minute run:
>
> One point for every inch of spark length
> 2 points for every MMC cap you explode
> 20 points if you strike the ground
> 50 points for striking the ceiling (indoor venues only)
> 75 points for setting your secondary on fire
>
> And double your score if your coil is solid state :)))))
>
> Steve C.
>
>
>