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safety cut off
The idea of a remote, 'understood by someone else' safety switch is excellent.
I can't think of a 'really good' way top extend that to those working
alone-alone. (The buddy system is a GOOD idea, in many risky endeavours.)
Where practical, a remotable (possibly low voltage) NO switch to be carried by
the operator will work. For many cases of tesla coil work this will be
impractical. (This technique is used in some pyrotechnic applications, being
required by some regulations: the operator must have a 'pickle switch' (from the
shape) which cuts off the progammer if the button is released...
True Story:
(My apologies to those who have read it before.)
A friend of mine (lets call him Roger), in his youth, laid hands
on a denist's xray machine, which was being scrapped. Being a tad
shy about the xray end, he rigged up a pair of hand held electrodes and
drew entertaining sparks (we are talking 100kvac here, 60 Hz).
One evening, he DROPPED one of the electrodes, on the (dirt) floor of
the shop. NOW EVERYTHING IN THE SHOP, _INCLUDING_ THE OFF SWITCH was at
100kvac relative to the electrode he had in his hand. He didn't want to
drop THAT for fear of making a bad situation worse. The transfoormer
WAS insulated for it, so it wasn't a short circuit, so the breaker
would not blow.
As it happened, his dad came out, figgered out what was wrong, and
cut the power from the main switch in the house. FOLLOWED by dumping
the transformer in a nearby, large, deep, body of water. If he had not,
come by, Roger would be standing there to this day...
regards
dwp