# 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

Steve C.

```