Original poster: coolbluesky <coolbluesky@xxxxxxx>
Hi Dr. R, all...
Although not directly Tesla related, I found an interesting article
about Van de Graaff generator safety, and physiological effects of
unintended electrical discharges here:
http://www.sserc.org.uk/public/Safety_Messages/safety2.htm
Certainly worth reading if planning a public demonstration. Makes
me cringe when I recall certain human "chain" demos at various
science museums I've seen.
Safe Zapping, everyone.
Karl
On Aug 28, 2006, at 2:54 PM, Tesla list wrote:
Original poster: "resonance" <resonance@xxxxxxxxxxxx>
The high school VDGRFs were all frictional excited and delivered
only 3 uA DC to the sphere. It isn't the charging current that is
the problem ---
it's the peak current that is delivered by the capacitance of the
sphere. Typically 40 Amps off a 14 inch dia. sphere.
We run terminals up to 30 inch dia. on our VDGRF at 750 kV but we
use a unique system of insulating the person from ground so he/she
doesn't discharge the current directly to ground. A 30 inch sphere
charged will deliver peak currents of 85 Amps for 1 usec.
I make and sell belts for VDGRFs and you don't need teflon for the
belt material.
You can discuss this with me at the Teslathon.
Dr. Resonance
As they say the only stupid question is the one unasked, but I was
wondering what is the largest VDG that could be built and still be
considered safe (tho perhaps uncomfortable) to be hit by? I came
across 400kV 10uA ones when I was in high school. Is that the
"safe" limit (considerig alot of goofball kids around it)? Was
thinking of using 1 of those 30" steel ball lawn ornaments I have
lying around to make one whenever I can find some suitable 4-6"
pullies (aluminum and teflon hard to find), just don't wanna kill
myself when I go to do the hair-standing stunt.
Mike
----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Sunday, August 27, 2006 7:27 PM
Subject: Re: small 4KV transformer, anyone?
Original poster: "resonance" <resonance@xxxxxxxxxxxx>
ED
Just rectify it. That's all you need to spray a VDGRF belt. We
use 5 kV, 2 mA xmfrs to spray belts up to 30 inches wide when
rectified --- it only takes 200-500 uA with a 30inch wide belt
and only 100 uA DC with a 6-8 inch wide belt. See our model
HV-750 (750 kV DC 30 uA output) at our website www.resonanceresearch.com.
Dr. Resonance
Original poster: Ed Phillips <evp@xxxxxxxxxxx>
Had trouble downloading the catalog so couldn't find out if
those things are used with esternal rectifiers. Any idea? I
have a unit which appears identical - picked it up at a swap meet years ago.
It was supposed to have come from a Xerox machine. I think with
a voltage multiplier it would be neat for charging VDG belts.
Ed