RE: spark plugs for gap??? (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Sun, 30 Sep 2007 11:42:44 -0400
From: "Lau, Gary" <Gary.Lau@xxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: RE: spark plugs for gap??? (fwd)

Putting multiple spark gaps in parallel won't work, as only the first
one to break down will conduct, and the others won't do anything.
Running a gap in a pressurized chamber would serve to increase the
breakdown voltage for a fixed gap width, or would permit a narrower
width for a given breakdown voltage, which may reduce losses.  But the
down side is that in a closed environment, cooling becomes a problem,
and providing airflow through the gap to aid quenching becomes slightly
more complex.  I think arcing in SF6 may produce toxic by-products.  I
do know that some commercial static spark gaps are filled with hydrogen,
as that improves quenching.  But in an amateur environment such as ours,
I'm not sure that the hazard of a hydrogen leak and explosion would be
worth the unproven benefit.

In short, it's much easier to just forget about using automotive spark
gaps in our application.  Just use relatively beefy electrodes that
don't tend to arc in a small, fixed area, and use forced airflow.

Regards, Gary Lau
MA, USA

> From: Chris Rutherford <chrismrutherford@xxxxxxxxxxxxxx>
> To: Tesla list <tesla@xxxxxxxxxx>
> Subject: Re: spark plugs for gap??? (fwd)
> 
> What about putting the electrode side in a pressurised chamber with
> something like SF6 or nitrogen and also putting about 4 or so in
parallel so
> that no single spark plug takes the whole current?  How much would
changing
> the pressure and gas would allow you to adjust the spark gap
> characteristics?
> 
> Thanks
> 
> Chris R