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Would this ionizer work? Answered

I built an ionizer in an old metal ATX power supply case.
My electricity is 230V 50Hz.
It uses 22x 2.2nF capacitors and 22x 1N4007 diodes.
The circuit is about this(with the activity indicator). I also added a small unregulated non-switching power supply for a fan that:
cools the transformer
forces air through the 5 needles.
The ionisation current calculates to 5uA/needle.
or 25uA total.
Important (or so I think) details are bold.


Jack A Lopez

3 years ago

I think Peter Tosh wrote a song about air ionizers,

Ionize it. Don't criticize it,
Ionize it yea-ah-yea-ah,
And I will advertise it
Some call it ozone,
Some call it oh-three,
Some call it negative ions...

and those are only lines I remember. Uh, what was this question about again?

Oh right! Air ionizers! Yeah. For something like that, it might be easier to find it in module form. There are places that sell such things.

For example, feeding the word "ionizer" to dx.com, returns a bunch of stuff they're selling


some of which are actual electric gizmos that make ions in air. There seem to be several different versions. There's the one that plugs into a car's cigarette lighter port. There's one made to plug into USB. There's one that runs on batteries that you can put in the fridge, to ozone-ize stinky odors.

I have also seen ionizers for sale in thrift stores. Usually that kind is the big air cleaner type appliance, and usually the reason it is there is because the filter is so dirty you could grow potatoes in it... but the ionizer module still works!

By the way, I apologize if the whole point of your question was specifically about a desire to build your ownDIY ionizer, and you aren't interested in buying one, no matter how cheap it might be.

cccp3Jack A Lopez

Answer 3 years ago

Such "thrift shops" don't exist in my country, and eBay or dealxtreme - never !

Jack A Lopezcccp3

Answer 3 years ago

That sounds rough, man! I mean living in a place without thrift stores. That must be like living in a place where there's no rain, or sunshine!

There was someone else recently asking this forum about voltage multiplier circuits,

and I guess I can point you towards the same place, I pointed him, which is this page,
which has some design hints for building voltage multipliers.

The circuit you posted looks like a Villard cascade with n=3 stages. This circuit would give, as its no-load output voltage, 2*n = 6 times the peak voltage of the waveform with which you are driving it.

The peak voltage of 230V mains voltage is 2^(1/2)= 1.41 times the RMS value. That is: Vpeak = 1.41*230 = 325 V

You say you want a circuit with 22 capacitors. What is that? n=11 stages?


22*(325 V) = 7150 V. OK. Sure.

But what happens when you load it? With say I=1e-6 A?

Using that formula from Jochen's page I linked to above,

I*T/C = I/(f*C) = (1e-6)/(50*2.2e-6) = (1/110) V = 0.009090 V

For n=11, ((2/3)*n^3+(1/2)*n^2-(1/6)*n^1) = 946

So the voltage drop for 1 uA is only (946/110) = 8.6 V

In that formula, voltage drop is proportional to current, so at 25 uA, the voltage drop is 25*8.6 = 215 V, still a small fraction of 7150 V, the no-load output voltage.

So, wow! Yeah. It looks like it will be pretty dangerous... if I did the math right. Maybe even if I didn't?

Other answers might have mentioned safety, and I also want to echo that sentiment. This thing, if built, is dangerous. DO NOT TOUCH it while it is turned on.


3 years ago

At ground level, ozone is a harmful, biologically-active pollutant. At minimum, it causes lung irritation, and longer-term or higher-level exposure can do some serious damage. There are rules about how long employees can stay in the same room as a photocopier without active ventilation etc.

If you are trying "improve" air quality, look to modifying the humidity or filtering out particulates. If you are wanting to play with high voltage, do something that is visually fun, like a Jacobs Ladder, or does something interesting like etch metal or play music.


Answer 3 years ago

A continual use of copier never lets the O3 short halflife self expire !!


3 years ago

About Ozone, Not a Triboelectric compound.
O3 has a half life of about 30 min.
OSHA does not get involved until you get 100 Lbs of it.
In your body it acts like CO Carbon Monoxide. That means it grabs a
blood cell and wont let go of it, decreasing your breathing efficiency for
a half hour. A hundred pounds of it would end your breathing altogether.

Ozone is activated oxygen. I make ozone machines to get the smell
of recent fire ( including cigarette smell ) out of bedrooms and
restaurant fish odors. The O3 basically finishes the burning process
non-exothermic and that is why we no longer can smell dinosaurs
flatulent :-). . . Cab companies use it to clean up stale cars and kill nite eggs...

The gas disperses fairly rapidly and with the short half life you are safe.
You would be breathing fractions of a gram the nose is very sensitive to ozone.
Nobody has died from lightning caused ozone yet.
The gas is used to replace chlorination of water in Hotubs and large factories.

Hospitals used the clear UV fluorescent tubes ( another generator of ozone )
mounted above eye level to disinfect air-born germs years ago.

There are people with the disease of asthma that react badly to the
tiniest odor of Ozone. You can use them as detectors :-)

I use a chicken wire inside an electric PVC conduit and cut liberal wires whose points are the source of arc energy to generate ozone.

Click the pic to view the entire image...


3 years ago

This thing mainly generates ozone, which is that high voltage musty smell you get from it. Similar to chlorine, Ozone is super reactive hence why it has a strong odor. I think it is also a carcinogen and a strong oxidizer. Really it would just pollute the air more than ionize it, unless you have a ozone filter to stick in front of it.


3 years ago

What is the purpose of the thing you build?
Be aware that a setup like that can generate massive amounts of ozone as well.
And you really don't want too much of that in the air you breathe.


3 years ago

Probably the essence is high voltage, very low current unless you want to kill someone.