Safety Thread, NST versus Pole Pigs

To: tesla-at-pupman-dot-com
Subject: Safety Thread, NST versus Pole Pigs
From: Dave Sharpe <sccr4us-at-erols-dot-com> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Thu, 10 Sep 1998 22:02:11 -0600
Approved: terryf-at-verinet-dot-com

Chip, Terry

I've been observing this post concerning NST/pole pigs dangers.
About 5 years ago, varmints were raiding my Dad's 1/3 acre garden.
Like Ed, we used an ignition coil, with moderate success but more
damage was being seen.  After much prodding from my Dad, we wired
1/2 of a 5kV -at-30 mA NST to hot wire, and gnded case to gnd rod and
AC safety ground.  About 2 nights later about 3 in the morning, my
parents heard a loud primeal scream.  In daylight, an adult possum
was found with tail wrapped around hot line locked to ground, dead.

Once high current is established ALL BETS ARE OFF.  I use 
INDUSTRIAL SAFETY GUARD LATCH RELAY CIRCUITS, and MULTIPLE E STOPS on my
high power equipment and discharge all HV paths. When I operate my
equipment, I sit on a INSULATED platform on a wooden floor.

I have a partially vaporized 15kV fuse clip on a stained oak base with
this simple remainder...

	COMPLACENCY KILLS!

Another brief warning, I know of an Electrical Supervisor
working on a large motor generator set powered by 2.3kV, 3phase (1.3kV
to ground). The bottom of the power switch was exposed and he was
checking wiring on bus when the METALLIC flashlight he was holding in
his right hand contacted 'C' phase, while his right
elbow was propped against the metal enclosure.  The problem; he
ASSUMED that the switch was top fed (normal USA - North American
practice); it was BOTTOM fed, and mistake two the panel had NO
WARNINGS THAT IT IN FACT WAS BOTTOM FED. And we all know the
possible end results of ASSUMPTIONS...
    
He was instantly KO'd, and momentarily regained conciousness (so fast he
didn't fail from his "stooping" position).  His right arm was useless
for 2 MONTHS, with nerve damage, and a 3rd degree burn the size of a
quarter on his elbow.  MAKE NO MISTAKES ABOUT IT GUY'S AND GALS; HE WAS
DA..LUCKY!!!

BTW, GI's have been killed in WWII with as little as 24VDC,
sweating like a pig, with boots in water filled craters working
on jeep electrical systems in the South Pacific...

REGARDS

DAVE SHARPE, TCBOR