HV shock modeling for Tesla coils

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Terrell Fritz <terrellfone@xxxxxxxxxxxxxxxxxxxxxxx>

Hi,

I recently pulled the PIRANHA SISG web site temporarily off-line 
until I could improve the safety warnings and data.  Since PIRANHA's 
charging system can be "thrown together" very quickly, I am very 
concerned that "anyone" could make a powerful (too powerful) system 
without much "HV safety knowledge".  With two old microwave ovens and 
a screwdriver, I could put it together in about 1/2 hour...  The SISG 
gaps still serve an "entry barrier" for many, but that could change 
very quickly as fully assembled boards become common...

In studying its safety and possible risks, I ran across this very 
nice safety paper:

http://www.nclabor.com/osha/etta/indguide/ig18.pdf

Page 4 has a simple human body model and a graph that "sort of 
determines" what various shock levels will do to a person.  Such data 
is easy to simulate with a circuit simulator to find peak and RMS 
currents that make be delivered to a person in contact with various 
parts of a Tesla coil system.  The "death vs. time" and levels that 
cause "fibrillation" as opposed to "just stopping" the heart are 
pretty well explained...

PIRANHA actually delivers far less power than I thought into various 
human fault loads (still easily deadly) but the added load is small 
on fuses and other conventional safety devices.  The output arcs 
still stop, but the circuit "happily" fries the person instead...

So I was wondering if the human model in Figure 1 has a more accurate 
version for voltages in the 5,000 to 25,000 volt range?  Also, if 
there is a larger graph like than in Figure 2 that would extend into 
the 20 amp range?  The graph could be extrapolated for 2 orders of 
magnitude, but that might not be very good.

Hopefully, I can fairly well "predict" the effect of touching various 
parts of the system in an effort to convince people that they really 
need to be "super safe" and fully enclose and insulate the thing like 
"I did" in my design.  I also must ponder the known deaths:

http://hot-streamer.com/TeslaCoils/Misc/Deaths.txt

and what safety measures could be taken "today" to eliminate the 
possibility of those specific accidents from recurring.

It would be nice if systems like PIRANHA were not only among the 
easiest and most powerful Tesla coils, but also among the "safest"!!

There will be a "temptation" to "skip" the NST and low powered coils 
by the "newbee" especially if systems like PIRANHA are "easier and 
simpler" to make...  I am not sure how to "empress" upon them the 
extreme dangers of such high powered state of the art things...  An 
advanced high powered coil, but the simplest to make...  It could be 
a very "deadly" combination...  Have to figure out how to "fix that" ;-)

All thoughts, public and private, welcome ;-)))  I guess it is time 
to push the safety warnings to "another level" now that we are 
getting "too good" at this stuff ;-)

Cheers,

   Terry

BTW - Interesting reading:

http://www-training.llnl.gov/training/hc/HVResearch/Grounding.html

http://pad39a.com/gene/shock.html

BBTW - I might have to "push" the "PIRANHA" trademark and patent 
thing now...  In today's world market, that is typically 
worthless...  But it does provide significant leverage in the case of 
the "abuse" of the technology...