Variac arcing = kickback? (fwd)
---------- Forwarded message ----------
Date: Wed, 14 Jan 98 21:46:42 -0500
From: Adam <absmith-at-tiac-dot-net>
To: tesla list <tesla-at-pupman-dot-com>
Subject: Variac arcing = kickback?
I decided to see what would happen if I added more transformer power to
my project, and I got disturbing arcing in the variac. The variac is an
18 general radio 120V variac, which was feeding the two 9kV 60mA
transformers on my project without incident. There is 8 feet of 14-3
cable between the variac and the project, and the ground wire in this
bundle is unused.
When I added transformer number three and fired up the coil, I got power
arcs between the variac's moving brush assembly and variac housing above
it. The arc is jumping about 3/16" so I'm pretty sure it's not just the
normal 140V there! What ever is sparking across this gap is followed by
a power arc from the mains, which melted a bit from both parts of the
variac. Somethings seems to be kicking back from the neons. This only
seems to happen when there is a breakout from the toroid. I am naturally
concerned for all appliances in the house, and I would like to correct
this problem ASAP.
What's going on here?