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HV Arc Resistance



Hi all,

I am still trying to figure out the hows and whys of the spark gap
for best design. My question pretains to the resistance of the
spark gap. In which way does the resistance of the gap increase
or decrease when compared to the distance? I.e: if my gap is
set twice as wide, does the gap resistance increase by a factor
of 2, 4, or ??  What (in comparison) effects would one see if I
built a (for starters lets say a static) spark gap with:

1.) Two electrodes with a distance X.
2.) A 10 electrode gap with a TOTAL distance X and
a gap to gap distance of x/10.
3.) Same as 2, except 50% of the gaps are x/20 and
the other half is x/5 (so total X is the same for all 3 cases).

(Right now) I am NOT (yet) interested in quenching or
other gap properties, but soley on the I^2R losses
involved in the gap setup.

For example, I am using a 10 electrode setup w/o any
quench help and get pretty good results. Awhile ago
(this was not with my 8" coil, so I donīt have a direct
comparison), I tried the Gary Lau method of vacuum
(well, mine was really pressure) quenching a two
electrode gap. My resulting sparks were a LOT less
than desirable. Yet, Gary is getting good results. My
setup was more of the makeshift kind, so it might
just be design failure on my part, but I am wondering
if my many gap design might have less (or more)
resistance, which in turn might be leading to better
results. Just FYI, I am running a 7500Vrms neon, a
67nF cap, around 600A peak primary current an NO
protection equipment except for a 3 piece safety gap
(set pretty wide) directly across the neon. Would
extra gap resistance be of help in harnessing the
inductive kicking effects, described on the List some
time ago? Is it good enough to just look at the lowest
resistance of the gap or must we view the resistance
per time period (much more complex) to fully
understand the gap?


Pondering in Germany,
Reinhard