From: "Tesla list" <tesla@xxxxxxxxxx>
To: tesla@xxxxxxxxxx
Subject: Re: Safety gap issues
Date: Thu, 24 Nov 2005 10:38:19 -0700
Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
Hi JT,
An unloaded NST is with no load attached to its output. 12KV is an
rms voltage which means that peak voltage is 17KV (Vpeak =
1.414*Vrms). A two bushing NSTs would have 6KVrms (wrt ground) on
each bushing (12KVrms between the two bushings) . Don't know how
you are measuring your voltage, but a ruler isn't the way to
go. Set each side of your safety gap with no load attached to the
NST. Then you can reconnect the TC primary.
If you use the mains ground for an RF ground, do not allow the
coil arcs to hit anything (walls, ceiling, etc) not directly
grounded to the TC secondary base. Use an outlet on a circuit
breaker branch that is not shared with anything else and use a
counterpoise. Also unplug anything electronic (TV's, computers, etc)
Best to go outdoors and ground your TC secondary base and strike
rail (if you have one) to RF ground (rod driven into the earth
with wet soil). If the NST is located with your TC (like just
under the TC primary), I would ground it (along with its
protection circuit) to RF ground and NOT to mains ground. If you
use a line filter, it should be grounded to mains ground. Your
variac should also be grounded to mains ground.
Original poster: "JT Bowles" <jasotb@xxxxxxxxxxx>
TWO THINGS:
1.) I know this is "very, very bad" but i use mains ground for my
entire circuit
2.) that being said, i have my NST, safety gap, and secondary all
linked to the same exact ground
*what do you mean unloaded NST? You want me to basically
disconnect the ENTIRE tesla circuit, after my safetygap? If i do
so, the safety gap will fire, up to aobut 15KV.
15KV is still enough to damage my transformer's(12,000/30 ma)
secondary isnt it? So, my safety gap would be useless set at such
a huge voltage. I think it should be set at about 1KV over what my
NST is set at. (my NST is set at 7,500 volts with my spark gap, so
the safety gap should be 8,500 to 9000 volts)
NO ONE HAS ANSWERED MY QUESTION YET THOUGH:
CAN MY EARTHED MIDDLE NODE ON MY SAFETY GAP BY REPELLING A SAFETY SPARK?
Not sure what your question means.
Gerry R.