Does this look like a good supply?

This forum is for specialized infomation important to the construction and safe operation of the high voltage electrical supplies and related circuitry needed for fusor operation.
Post Reply
beatlemaniacjng
Posts: 20
Joined: Tue Apr 03, 2012 12:04 am
Real name:

Does this look like a good supply?

Post by beatlemaniacjng » Fri Jul 27, 2012 1:08 am

So, I found this tutorial on instructables. I think it should work. It gives high enough voltage, and I can tap it at different points, for the different potentials on the electrodes. After each tap I have to modulate it (it being the current) in someway to account for the different polarities of the electrodes, but this seems like it should work.

http://www.instructables.com/id/High-Vo ... ultiplier/

Tyler Christensen
Site Admin
Posts: 551
Joined: Tue Feb 24, 2009 2:08 am
Real name:

Re: Does this look like a good supply?

Post by Tyler Christensen » Fri Jul 27, 2012 1:13 am

It would work (and is how it's usually done) if you were driving it from a high frequency transformer, but at 60hz from a MOT/NST/OBIT/etc. to get fusion currents you would need huge capacitors in the multiplier. This has been done with series strings of Microwave Oven caps by members of this forum, but I can't say I'd suggest it especially if you don't have a lot of high voltage experience, as it is remarkably hazardous.

There is quite a bit of documentation of people's multipliers on this site, search around.

User avatar
Chris Bradley
Posts: 2930
Joined: Fri May 02, 2008 11:05 am
Real name:

Re: Does this look like a good supply?

Post by Chris Bradley » Fri Jul 27, 2012 6:14 am

Not all OBITs are born equal, and some do give out multi-10kHz outputs. See the comment/link I put in; viewtopic.php?f=11&t=4871#p31892 .

Of course, you cannot power something from nothing - if the OBIT is rated at 50VA and you are pushing out 50kV through a stack, then you can only expect 1 mA output (and that's presuming a 100% efficiency too! - call it 0.5mA for 50% efficiency). As more current is drawn, so the volts pull low.

It should also be borne in mind that the power output, even of a 20kHz stack driven from a 50Hz OBIT, will have a 50Hz oscillation to it as the OBIT (however it is internally wired) is unlikely to smooth out a full power draw from it, over a mains cycle.

beatlemaniacjng
Posts: 20
Joined: Tue Apr 03, 2012 12:04 am
Real name:

Re: Does this look like a good supply?

Post by beatlemaniacjng » Fri Jul 27, 2012 4:05 pm

Plus, even plugging in a regular 120vac outlet at 60hz to the equation he gave, I was pulling 2kv at seven sets. 20kv will be much to expensive and impractical, so back to the drawing board.

beatlemaniacjng
Posts: 20
Joined: Tue Apr 03, 2012 12:04 am
Real name:

Re: Does this look like a good supply?

Post by beatlemaniacjng » Sat Jul 28, 2012 12:02 am

So update; What I need to do is take a transformer (OBI for example) and run it through a multiplier.

Post Reply