130kW Coil -- First Light
From: Greg Leyh [SMTP:lod-at-pacbell-dot-net]
Sent: Thursday, January 29, 1998 9:19 AM
To: Tesla List
Subject: 130kW Coil -- First Light
After what has seemed like an eternity of preparation,
testing and adjustments, I connected the main xfmr set
in the delta-delta config (1/3 normal power) and threw
the switch early Wed morning, around 03:00.
The output streamers, which extended outwards about
2 to 3 electrode diameters (14 to 21ft), seemed much
bushier than did my last coil, and exhibited a lot of
simoultaneous branching from the main stem, much closer
to the discharge electrode. Some of this arc appearance
might have been due to my perspective however, as I was
standing at the vault door, directly under the top sphere.
Unfortunately I was not equipped to photograph the test;
In fact, I hadn't even planned to run the coil that evening.
It's just that things were going so well that night, and
the skies were perfectly clear, an unusual sight since our
rainfall has been almost double the norm so far this year.
Several problems were discovered during this unscheduled
Power Consumption - the mains power draw was about
2.5 times what it should have been for this configuration.
Current waveforms for the charging reactor were not
available since the #-at-*! battery-powered Fluke Scopemeter
kept turning itself off whenever the coil was energized!
The excess power probably ended up in either the streamers
or the rotary gap(more likely), as no excessive heat or
flame were observed coming from any other components.
Shocks to Operator - I would get mild shocks from the
control panel during operation, so using a distant ground
as a reference, I checked the potentials on the panel
case, and on my person.
Result: panel - 10VAC RF, me - 400VAC RF!
I was shocking the panel, as it turns out. Hopefully,
the electric fields will be friendlier when panel and
operator are 60ft distant. Otherwise some vertical
screening may be necessary at the control panel.
These problems will have to be addressed before the
main xfmrs can be configured for delta-star (hi-gear).
Once the machine appears to ready for high-power
testing I'll let the List know, for the benefit of
any 'potential' visitors.