P.S. His claimed arc length of 1-2cm would indicate more like 20-50kV max.
Best regards, Spehro Pefhany
"....voltage presence." ???!!!
I've NEVER heard that phrase before! Good one. Just reeks of 'high impedance'
At first I laughed, and then reread that line. That person is either telling the truth or totally prevaricating [couldn't spell the participial case for lie] nothing in between.
That thing has to be really, really low current. trying to get 10uA is 4W load! or even 1/2 w at 1uA, more likely takes 300 mA !
400kV at 1uA is some pretty high Z, at 400 gigaohms. now using the rule of thumb of measuring with more than 10:1 Z...Do you have an 'electrostatic' meter?Or, a leyden jar and transfer to measure, the decay trajectory will show you what the original voltage was.
Totally forgot! Ask the supplier for the 'proper' method to test for 'incoming inspection' You'll also get insight into their thinking.
An inductor can certainly make 350VDC, as in this faux "CD" ignition...
...Jim Thompson
12VDC to 350VDC, nearly 30:1 >:-} ...
...Jim Thompson
But not 450 yet.
OK, but that's approaching zero efficiency; all the energy winds up in fet+inductor capacitance and core losses. That might be OK in some applications.
Ooh, crabby lately.
I guess your issues don't have anything to do with the subject of this thread, either.
From 12 volts. Make it do 450 from 1.5, using realistic parts.
Cool. How big was that coil?
Word salad. Do it.
OK how about an oscillator into a cockroft-walton voltage multiplier. (maybe with a transfomer coupled oscillator... for a bit more gain there... gotta turn on those diodes) Mind you I don't really know how to make a 1.5 volt oscillator. Maybe if I could have 3V to start with :^)
George H.
On a sunny day (Mon, 10 Feb 2014 06:38:55 -0700) it happened RobertMacy wrote in :
But its _AC_ that comes out...
Capacitive method perhaps, can make a plate capacitor of a fraction of a pF, capacitive divider, scope...
plate big cap cap HV - C1 --- C2- GND AC | scope | GND
On a sunny day (Mon, 10 Feb 2014 08:01:39 -0500) it happened Spehro Pefhany wrote in :
Ah, liquid divider, I think I will try a capacitive divider.
On a sunny day (Mon, 10 Feb 2014 08:13:20 -0500) it happened Spehro Pefhany wrote in :
Nice page, downloaded teh pdfs, looks like about 30 cm with spehres for 400 kV.
As writing this reply, remembered the battery was a D cell, not a AA and the coil was LARGE, perhaps a solenoid starter coil. Remember also the prof said the current took time to ramp up to significant value, which matches his other comment about going through a lot of batteries.
Yeah, don't use a metal ruler. ;)
Yes, very good page. In his first paragraph, he lists ALL the effects that change a spark gap, except an important one. Light.
Photonic energy can substantially shift the firing of an arc, too. Based upon experiemcne, we shoved a bunch of those gas discharge tubes that fire at 400 volts down into a tank of oil to suppress damaging voltages in a
200kV isolated system. These discharge tubes were designed [German designers] to arc at 400 V [within a spec range] weren't even firing at 1kV ?!! later we found the problem was NO LIGHT, being dark there wasn't that 'added' energy and they just didn't arc. The manufacturer, at first, disputed our findings. The problem is that all their evaluation measurements were confirmed by their technician in their well lit lab, and after all, how many people sit in a dark room to measure stuff?I think later versions are doped with radioactive materials [pre-seeded so to speak] and such to ensure proper firing under any light conditions.
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