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Precipitator power supplies?

Posted: Tue Jun 06, 2017 1:46 am
by ian_krase
One type of power supply (either of the "hurts if you drop on foot" or "burns out semiconductors" type) that I haven't seen discussed here very much is a precipitator supply. As far as my research can tell, these devices need to maintain fusion levels of voltage (>40 kv seems common) while having fusion levels of current leaking into the dusty air due to Corona and huge plates.

And I found one for a *very* good price. It looks nearly identical to the one in this thread: ?f=6&t=9355&p=63246&hilit=Precipitator with an array of flybackish-looking transformers. However, I don't know if that guy was able to actually provide fusion levels of power. The one I found is rated at IIRC 450 watts


Is this a viable or nearly viable supply type, or is it another short-circuit-current/open-circuit-voltage/peak-pulse-power dodge?

Re: Precipitator power supplies?

Posted: Tue Jun 06, 2017 5:57 am
by Jerry Biehler
I have worked on pretty big units in machine shops and the power supplies will supply no where the current needed for a fusor. Plus they have arc detection that shuts down the power supply when it sensed abnormal loads.

Precipitators are designed not to have corona, that causes ozone and nitrous oxide which is bad.

Re: Precipitator power supplies?

Posted: Tue Jun 06, 2017 6:09 am
by ian_krase
Huh. I'm not terribly surprised. What justifies the huge current ratings, then?

Re: Precipitator power supplies?

Posted: Tue Jun 06, 2017 7:59 am
by Jerry Biehler
Larger one for industrial units might work. I really am not sure. I just wouldn't expect much from a cheap chinese power supply.

Re: Precipitator power supplies?

Posted: Tue Jun 06, 2017 8:39 am
by ian_krase
Ok, OK, I'll break the secrecy. It is indeed cheap and Chinese, but it appears to be small quantity surplus, not something being sold at normal market value. So I don't really know. The claimed capabilities are pretty significant, but I can easily understand it not living up to them.

Could be interesting even if it only provides a fraction of the current.

It's this one: http://www.ebay.com/itm/High-voltage-el ... SwY3BZGnHF

Re: Precipitator power supplies?

Posted: Tue Jun 06, 2017 7:12 pm
by John Futter
Ian
yes you should have posted this at the beginning
yes that is capable of a least 460 watts if not a lot more.
It looks so simple that i doubt that it has current limit but a good series resistor appropriatly sized will protect the supply.
you could get more control by feeding it with a voltage current limited DC 200 -350volt supply
those flybacks are good to about 150 watts each --depends on caps an diodes on the output as these will be the limiting factor
Be cyee warned these are meant to swing about earth ie you will have -30kV 0 +30kV although there is no apparent earth connection.
earthing one side might strain the creepage on the pcb and transformer winding to core with little attention being paid to corona possibilty

Re: Precipitator power supplies?

Posted: Tue Jun 06, 2017 7:21 pm
by ian_krase
So you say that it has a center tapped DC output? Huh. Could be useful for some types of accellerator....

Re: Precipitator power supplies?

Posted: Tue Jun 06, 2017 7:59 pm
by John Futter
ian
Read again
No I did not say it had a centre tap
but it is designed to swing about earth albeit earth being phantom
+- 30kV is very different from 0 60kV for the reasons in my earlier post

Re: Precipitator power supplies?

Posted: Wed Jun 07, 2017 3:34 am
by ian_krase
Oh, I get it.

Maybe needs the mineral oil / paraffin / whatever treatment?

Re: Precipitator power supplies?

Posted: Wed Jun 07, 2017 10:55 am
by Dennis P Brown
I am concerned that the voltage swings which means the average power (in the very high range say 25- 30 kV) is going to be low and not what you see as the input power for the main supply. I seriously doubt the unit will be good for a first time user; I would speculate that this is rather an interesting experiment for someone that has a proven detector (i.e. known calibration and/or noise level for a given neutron count) and has created neutrons in a proven machine. Yes, the price is acceptable as long as one doesn't mine it not creating neutrons ... . By the way, if it did only produce a fraction of the current (as you suggest) than 460 watts quickly falls below the required threshold for a viable fusor - yes, a good/outstanding detector can partly make up for lower current but again, not a good way for someone with a new fusor and no neutron experience.