# Re: [TCML] Voltage on the Streamers

﻿David Varas & I had a great conversation on another social media platform & here’s my initial response:

The Tesla coil spark is a completely different animal from static electricity, direct current, or mains frequency sparks!!!

This is because there is an “arc channel” formed from the initial spark, ionizing the air, allowing the next spark to grow in length.  This process eventually is in a steady state, so to speak & the spark cannot grow longer.

Greg Leyh (of Lightning on Demand) is probably the leading expert in high power Tesla coil research & he explained this to me at a Teslathon in New York when I first had the pleasure to meet & chat with him...

His rough estimate or “rule of thumb”
relationship between output voltage and streamer length is 200kV/m.

..........
Gary discussed with me two approaches regarding approximate output voltage itself:

1).  Calculation:  From conservative of energy we know 1/2 (Cp)Vp^2 = 1/2(Cs)Vs^2.

Allowing for 25% losses this becomes CsVs^2 = 0,75*CpVp^2 and...

Vs = SQRT (0,75*Cp/Cs) or...

Vs ≈ 0,866*SQRT (Cp/Cs)

2).  By measurement:

Install a wide-band current transformer in the secondary’s ground to earth connection.

Observe with proper recording instrumentation, the corresponding current.

The secondary reactance is calculated by Xs = 2*pi*fs  (this neglects secondary DC resistance).

The output voltage, Vs is what we “see” across the above reactance, or

Vs ≈ 2*pi*fs*Is
..........
Therefore, whatever his experience is, I’ll agree with him.

https://www.lod.org/research/research.html

Sent by Mačak's humble servant.
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