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Re: Got Shocked

Tesla List wrote:
> 
> Original Poster: gweaver <gweaver-at-earthlink-dot-net>
> 
> I have seen pics of other people doing this so I tried it myself.  Take a
> look at this pic and you will see what I mean,
> http://members.aol-dot-com/krampf/watt.html. I got zapped. I have done this with
> a VDG several times but this is the first time with a TC. I stood on a 5
> gallon plastic bucket, the plastic bucket is my insulator.  I turned on my
> 750 watt TC and set the variac to about 150 watts.  I can get 6" sparks to
> my hands and fingers but I can not feel them at all.  I turned the power up
> some more and still I can barely feel a 18" sparks.  With my hand on the
> toroid I can not get any sparks to radiate off of my other hand into the
> air.  Tried retuning the TC but still can not get any sparks to radiate from
> the other hand.  I turned the power down to 150 watts again and with one
> hand on the toroid I held the other hand out to a target.  ZAP, knocked the
> -at-#$% out of me. Glad I had the power turned down.  I know by touching the
> toroid with my hand my body acts like a top load and changes things so the
> primary will have to be retapped.  I don't think I will try this again until
> I learn how its suppost to be done. Does anyone know how this works?  I am
> gun shy now, not sure I want to try it again.
> 
> Gary Weaver

Gary,

I bet that was quite a nasty surprise!! You never want to pass a
discharge from your system through your body and then to ground, since
the peak current can be in the multi-ampere range... and to add further
insult, it's essentially a DC capacitor discharge! For example, if the
combined capacitance of you and your coil is, say 75 pF, and the
fully-loaded peak output voltage hits 200 kV, the peak electrostatic
energy will be about 1.5 Joules. Now, suppose you accidentally discharge
this through your body through a connecting streamer to ground. This is
comparable to taking a large 2500 pF 40 kV doorknob capacitor, fully
charging it to 35 kV and then purposely discharging it through your
body! Although this would probably not kill you, the resulting muscle
contractions may cause subsequent injury... and it's certainly something
you really wouldn't look forward to doing again! 

BTW, forget about all the "stuff" you may have heard about RF and skin
effect. While this does apply to RF and metallic conductors, it simply
does not apply to your body at Tesla Coil frequencies. Virtually all of
the RF current from a Tesla coil will flow THROUGH your body, and not on
your skin. While the output current from a coil may not be "felt", it's
simply because your nerves don't directly respond (with pain warnings)
to RF.  It's similar to not being able to "hear" ultrasonic sounds -
your nerves simply aren't responding to what could be damaging levels of
current flow. This means that, particularly with a CW coil, you can
literally cook internal nerves and tissue without feeling any
discomfort... at the time. Shortly thereafter, you may experience
significant joint or muscle pain, tingling, or numbness. In more severe
cases you may get impaired nerve or muscle function lasting for weeks or
months. The latter has been reported by coilers accidentally taking a
direct "hit" from larger disruptive systems.

If you are well insulated from ground and touch your toroid, your body's
capacitance will add to that of your system, significantly lowering its
resonant frequency, and significantly lowering its peak output voltage
(but NOT its output energy!). Both Robert Krampf and Brent Turner are on
this list, so they can comment firsthand on any specific techniques they
may use/recommend (although I doubt that either will recommend that
other list members actually duplicate these demonstrations). 

If you look on Brent's website:
http://www.funet.fi/pub/sci/electrical/tesla/pictures/turner/brent_4.jpg
he connects a wire from the toroid directly to a chainmail glove in his
hand, so that none of the streamer current acually passes through his
body. However, I also remember Brent relating a recent incident where a
direct discharge accidentally came from his elbow, resulting in a
muscle-spasm related injury, and a severe electrical shock. 
BTW, the author Henry Transtrom ("Electricity at High Pressures and
Frequencies") used to do similar demonstations in the 1920's... until he
became Tesla Coiling's first statistic during an on-stage accident.

SAFE coilin' to you!

-- Bert --