RE: peak current when spark gap fires

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>

Say was does the SQR of 2 come from. It easy to imagine .707 * peak or
rms/.707 hmm Root Means square...to the Inet. Never mind the math gets out
there for a "collection of n".

Elementary but I don't remember covering it that way.

-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx]
Sent: Friday, October 20, 2006 6:10 PM
To: tesla@xxxxxxxxxx
Subject: Re: peak current when spark gap fires

Original poster: Vardan <vardan01@xxxxxxxxxxxxxxxxxxxxxxx>

Hi,

There is a list of such formulas here:

http://hot-streamer.com/temp/FormulasForTeslaCoils.pdf

The formula you want is at the top of page 6.

However, you already figured it out almost correctly ;-)  The thing I
would change is the actual voltage the gap fires at.  If your NST is
rated at 12000V RMS then the peak voltage will be 12000 x SQRT(2) =
16970 V.  So the primary peak current is probably 245 amps.

Cheers,

         Terry


At 09:23 PM 10/19/2006, you wrote:
>Hello. I am new to a lot of this, so I want to make sure I got this
>correct. Did I do this right to find the peak current when the spark
>gap fires? Assuming the only inductance in the calculation is the
>primary coil....
>
>Surge impedance = sqrt(Lp / Cp)      my primary is around 48.029uH
>according to calculations, and capacitor is
>0.01uF    so  sqrt(0.000048 / 0.00000001F) = 69.282     and then
>current peak = Vp / Surge impedance  so  12000 / 69.282   = 173.205
>amps?   This is most likely way wrong :P