Re: TC Question and Discharge Safety

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Bert Hickman <bert.hickman-at-aquila-dot-net> 

Richard,

Most professional coilers use special techniques which allow them to 
prevent RF current from flowing through their body. They use protective 
gear ranging from chainmail meat cutting gloves and hidden wires to entire 
electrically conductive "shark suits" or similar Faraday Cage suits, such 
as Dr. Megavolt. In the referenced video clip, the person has his hands 
carefully elevated so that low current air streamers mostly emerge from his 
metal-gloved fingertips. Since his chain metal gloves are electrically 
connected to the terminal he's sitting upon, no RF current is actually 
flowing through his body.

However, if you look very carefully, you'll also notice that small 
streamers sometimes emerge from the performer's left kneecap because the 
relatively small platform diameter doesn't quite provide the necessary 
shielding for this long-legged performer. Unprotected knees, elbows, and 
noses can sometimes become undesired sources for streamers. The resulting 
shock/surprise has been known to cause involuntary muscle contractions 
which can throw the performer off the platform, especially if the discharge 
"connects" to ground. One rather well known demonstrator has broken his 
wrist in this manner.

Suffice it to say that professionals know the risks and they take special 
precautions to minimize them. An amateur coiler will usually survive 
accidental or controlled "hits" from even a medium sized coil. But most 
truly experienced coilers tend to avoid taking streamer hits on purpose.

Happy New Year!

-- Bert --
-- 
--------------------------------------------------------------------
We specialize in UNIQUE items! Coins shrunk by Ultrastrong Fields,
Lichtenberg Figures (electrical discharges in acrylic), & Scarce OOP
Technical Books. Stoneridge Engineering -- http://www.teslamania-dot-com
--------------------------------------------------------------------

Tesla list wrote:
>Original poster: "Richard Modistach" <hambone-at-dodo-dot-com.au>
>so i take it the guy sitting on top of the tesla coil in the hvfx
>video,
>http://www.hvfx.co.uk/video/lightningman.mpg
>is slowly toasting himself to an early grave?.
>regards
>richard
>aus.
>
>----- Original Message -----
>From: "Tesla list" <tesla-at-pupman-dot-com>
>To: <tesla-at-pupman-dot-com>
>Sent: Thursday, January 01, 2004 10:15 AM
>Subject: Re: TC Question and Discharge Safety
>
>  > Original poster: dhmccauley-at-spacecatlighting-dot-com
>  >
>  >
>  > There is no such tesla coil capable of what you ask.  There are always
>  > dangers involved.  Sure, you could take a metal rod and pull the arc of
>  > most small tesla coils (up to about 4kV/30mA) as well as VTTCs and STTCs
>and
>  > not really feel anything at all, but the RF currents are still
>  > flowing through your tissue and causing damage.  Due to the high frequency
>  > nature of the electricity, your nerves do not feel the current, but be
>  > aware,
>  > that damage is likely being done.
>  >
>  > Also, many will state that skin effect will protect you from the dangers
>of
>  > high frequency tesla coil discharges, but that is a myth.  Skin effect
>  > really
>  > has no effect on the human body.  Most of the RF current is flowing
>through
>  > your body and not on the skin.
>  >
>  > So when you ask if its safe to come into contact with the discharge of a
>TC,
>  > the answer is, no.  Sure, you may not feel any immediate pain
>  > when doing something like this, but doing this repeatedly may cause long
>  > term damage which may not show up for years to come.  Its always
>  > best to watch from distance and not become part of the demo.
>  >
>  > Dan
>  >
>  >  > It appears I mis-stated my question. I am aware of the safety issues
>with
>  >  > the output of the NST or any AC source. What I was wanting to know is
>  >  > whether or not there is any size TC that it is safe to come in contact
>  > with
>  >  > the output streamer, baring a strike to the primary while touching a
>  >  > streamer.  If so, what are the specs for such a coil?
>  >
>  >
>  >  > > > Can someone tell me the power range (ie. volt/amp rating) that is
>  >  > > > safe.  I am assuming that there is a point at which they become
>  >  > >potentially
>  >  > > > lethal and below that point they are safe. I have a 7.5 KV NST I
>would
>  >  > >like
>  >  > > > to do something with but I don't know if I can use it for the this
>  > type
>  >  > >of
>  >  > > > coil. Thanks in advance for your assistance.
>  >  > > >
>  >  > > > Emmett
>  >  > >
>  >  > >You are incorrect in your assumption.
>  >  > >Any voltage above 30V or so is considered hazardous at least by
>various
>  >  > >safety standards etc...although this
>  >  > >is debated among different schools of thought.
>  >  > >Although voltage doesn't kill, it is current that does the job.
>However,
>  >  > >given some value of resistance in the human body, the higher the
>  >  > >voltage, the higher the current.
>  >  > >
>  >  > >There are no safe NSTs.  Any sized NST has the capacity to injure or
>even
>  >  > >kill someone especially when connected to
>  >  > >a circuit that contains capacitors such as a Tesla Coil.  For example,
>if
>  >  > >you turn off your NST power at the peak point and have
>  >  > >a primary tank capacitor with no or little bleeders, the primary tank
>  >  > >capacitors could be fully charged to the peak output voltage
>  >  > >of the NST.
>  >  > >
>  >  > >Also, there are many things that will affect how dangerous a NST can
>be.
>  >  > >For example, the impedance (resistance) of the human body
>  >  > >for one.  The resistive path of the human body is greatly affected by
>  > many
>  >  > >things including moisture, point of contact, and physical skin
>thickness
>  >  > >(such as
>  >  > >broken skin or sores, callouses, etc...)  While you may survive to
>coil
>  >  > >another day with a shock from a 15kV/60mA in dry, normal conditions,
>your
>  >  > >life
>  >  > >may be abrubtly by a small 4kV/20mA NST if you happened to touch the
>high
>  >  > >voltage through a sore or wet hand or something.
>  >  > >
>  >  > >The important thing here, is that no high voltage is safe and that
>  > includes
>  >  > >any type of NST whether its a small 4kV/10mA unit or a large 15kV/60mA
>  >  > >unit.
>  >  > >All should be treated with the utmost respect and no one should become
>  >  > >complacent around them.
>  >  > >
>  >  > >The following document on my website describes electrical safety and
>its
>  >  > >effects on the human body.
>  >  > >http://www.easternvoltageresearch-dot-com/datasheets/safety.pdf
>  >  > >
>  >  > >Dan
>  >  > >
>  >  > > > I am wanting to build a small coil that would be safe to run
>connected
>  >  > >to
>  >  > > > the supply ground and also safe if someone should come in contact
>with
>  > a
>  >  > > > streamer. Can someone tell me the power range (ie. volt/amp rating)
>  > that
>  >  > >is
>  >  > > > safe.  I am assuming that there is a point at which they become
>  >  > >potentially
>  >  > > > lethal and below that point they are safe. I have a 7.5 KV NST I
>would
>  >  > >like
>  >  > > > to do something with but I don't know if I can use it for the this
>  > type
>  >  > >of
>  >  > > > coil. Thanks in advance for your assistance.
>  >  > > >
>  >  > > > Emmett
>  >  > > >
>  >  > > >
>  >  > >
>  >
>  >
>  >
>
>.