"Paul Victor Birke" wrote in message
...

Be assured, EDMs, particularly modern ones, run at open-circuit voltages
well below those suggested by some here. The one I'm most familiar with
had
a maximum open-circuit voltage of 350V. That was 20 years ago. But there
have been EDMs that run well with a maximum open-circuit voltage of 90V.

Most interesting, tending to make Paschen's Law somehow not practical
here or over-ridden !!

I suspect it's just some additional phenomena that we aren't accounting for
here. If you're interested, here's a technical paper about EDM pre-spark
phenomena that may clear it up. I believe it concerns liquid dielectrics,
and they used a 600V one-shot power supply to create the observed events,
but it may suggest to you what's happening with air dielectric:

http://www.uni-magdeburg.de/iget/pub...PaperNo_89.pdf


Happy New Year


To you too, Paul.

--
Ed Huntress
(remove "3" from email address for email reply)