How to Make a Negative Ion Air Ionizer

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How to Make a Negative Ion air ionizer by petercd on August 8, 2010

Table of Contents How to Make a Negative Ion air ionizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1

Intro: How to Make a Negative Ion air ionizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2

Step 1: Components and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2

Step 2: Full-Wave Ionizer Materials and Component Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4

Step 3: Half-Wave Ionizer Materials and Component Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5

Step 4: Carbon Fibre vs Pins for high voltage grid. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7

Step 5: Speed wiring tip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8

Step 6: Full Wave Ionizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Step 7: Full wave component assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Step 8: The Optional Fan and its power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Step 9: The HV pin grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Step 10: The Half Wave Ionizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Step 11: The End Cap, HV Grid and Neutral Grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Step 12: Final Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Author:petercd general bloke type of tinkering

Intro: How to Make a Negative Ion air ionizer Two models will be shown, one full-wave rectified and the other a half-wave rectified negative ion ionizer. Featuring an optional fan on the full-wave model. Benefits of negative ions supposedly include • freshen and purify the air • help lift mood • alleviate depression including winter depression(SAD) • eliminate most tiny particles suspended in the air (indoors) CAUTION HIGH VOLTAGESpresent in both devices is high enough to induce a bad case of temporary Tourettes. ie twitching/profanity. Be aware of the hazards when working with loose CARBON FIBRE filaments if using this option for high voltage grid instead of pins.

Image Notes 1. half wave version 2. full wave version

Step 1: Components and Design Tools required : soldering iron and solder. screwdrivers, flat and star cordless drill. hot melt glue gun. Optional tool: wire wrapper. The full wave rectified version has better performance but is a bit noisier if using the optional fan. The fan is a 60mm x 60mm CPU 12 brushless fan which I'm driving at 5v to reduce current consumption and noise. The half wave version uses fewer components and less current, the smaller size is also trickier to build. In both versions the negative band on the diode must point towards the ac voltage input. If you follow the green arrows on the component diagrams, you will first encounter the negative side on the diode first, indicated by the white band.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. neutral grid on half-wave version, but ground grid on full-wave version.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Step 2: Full-Wave Ionizer Materials and Component Layout Materials required for full-wave version : 2 x 10meg ohm resistors. (limit output current for safety) 40 x diode 1N4007. 30 x capacitor 100nF 275V class x2 suppression. 1 length 350mm ega tube trunking. 2 ega tube end caps for trunking. 4 x self tappers for end caps. low amperage hookup wire, ATX power supply type wire is fine. 1metre 3 core 220v ac lead. standard pins (or carbonfibre) for high voltage grid. Optional components 60mm x 60mm 12V dc fan, old cpu fan works well. finger guard for above fan. old cellphone charger +/- 5V dc to power fan. small switch for fan, necessary for silent operation.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. just to indicate flow direction, and encountering neg band on diode first

Step 3: Half-Wave Ionizer Materials and Component Layout Materials required for Half-wave version: 50mm PVC pipe approx 330mm long. 2x 50mm pvc end stops. 2x 50mm tube joiners, necessary for fitting the end stops. 2 small self tappers, for fitting the removable end stops. 1metre twin core 220v power, 5 amp is fine. 2 x 10meg ohm resistors. (limit output current for safety) 30 x diode 1N4007. 30 x capacitor 100nF 275V class x2 suppression. standard pins (or carbon fibre) for high voltage grid.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. indicating flow direction, and encountering neg band on diode first

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Step 4: Carbon Fibre vs Pins for high voltage grid. The two components of an air ionizer are high voltage and sharp points on the high voltage grid. I prefer carbon fibre (CF) due to the thousands of very small points from which the negative ions escape, versus just one compared to a pin. However my method of obtaining said CF might seem a bit dodgy to some folk. What I did was use a broken CF tube from one of my RC planes(crashed :( ) and broke 3 small 2mm x 20mm long splinters. I briefly set the tips alight and then blew the flame out, then I flicked the tips clean of loose ash/ fibres. Try not to breathe these loose fibres or the result might be a persistent cough . Once clean the pieces were wrapped with thin copper wire, to act as a pigtail for soldering electrical connections to, and then shrink wrapped. I keep the working tips about 3mm long to prevent them flaring out and shorting out on something. Initially I sharpened standard dressmakers pins which worked well in the full wave version, however I might still consider an upgrade to CF tips for the full wave ionizer,

Image Notes 1. CF tube host 2. pieces about 2mm dia

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. spread out and clean loose fibres

Image Notes 1. not yet shrink wrapped for clarity. 2. short 3mm tips to prevent flaring

Step 5: Speed wiring tip After completing the full wave ionizer, I discovered things go a lot faster if you're able to acquire a wire wrapper, seen in the pic below. I use the one leg of the cap as the post to wrap the other 3 leads on. It is also possible to make do without the wrapper and just use the same technique, but its just more fiddly and takes longer even though the end product will look neater.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. step 1: use one leg of the cap as a post to wrap the others

Image Notes 1. step 2: wrap the 1st diode leg

Image Notes 1. all 4 leads wrapped

Image Notes 1. these will be soldered and snipped shorter

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Step 6: Full Wave Ionizer The full wave rectified ionizer seems to work a bit better than its half wave brother, the optional fan also boosts performance, although some folk seem to think it gets in the way of the ion flow, possibly absorbing quite a few to the detriment of better performance. The performance increases greatly with the finger guard grounded, which is why the fan is reversed with the finger guard facing inwards.

Image Notes 1. ac input

Image Notes 1. this grid is not electrically connected

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Step 7: Full wave component assembly First all the capacitors were glued end to end, 3 rows, then the diodes were laid on top and soldered. Observe the correct diode polarity with the white neg band pointing towards the ac input side. The ground lead must be on the middle row of caps, and either outside row for live or neutral. Once the components are soldered I put blobs of glue on the sharp soldered points to reduce corona discharge which improves HV (high voltage)performance. The completed HV voltage multiplier array is then glued to the side wall of the ega tube, which also assists in component separation to prevent the high voltages from skipping across components.

Image Notes 1. blue AC neutral input 2. earth/ground input 3. red AC live input 4. the 10M ohm safety resistors

Image Notes 1. sharp points will need to be insulated

Image Notes 1. one of the 10M ohm safety resistors

Image Notes 1. hot melt glue to reduce corona, improve performance

Image Notes 1. HV array glued to sidewall 2. fan switch and psu 3. fan

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Step 8: The Optional Fan and its power supply I used a nokia 5V charger although any cellphone charger rated at 5V will work, 4.5V doesn't seem to however. A 60 x 60mm fan fits inside the ega tube stopend, which makes it easier to mount the switch, which is spliced into the dc output wire, nearby. The fan will not work with its power reversed, so connect it up and see which way it blows. Then mount it such that it sucks the air out of the ionizer, with the finger guard on the inside, which is grounded to the green earth lead of the ac input. Its best to remove any metal in the ion path including the metal foil sticker on the fan blades, it could absorb negative ions greatly lowering performance.

Image Notes 1. pvc mounts for high voltage grid 2. sharpened pins for HV grid 3. remove any metal in ion path including this sticker

Image Notes 1. fan switch 2. fan psu 3. this green earth wire goes to the finger guard

Image Notes 1. best to remove this metal sticker 2. power for fan 3. green earth/ground to finger guard Image Notes 1. the business end 2. cell charger 220v power on

Image Notes 1. fan & HV grid 2. fan switch 3. capacitor diode voltage multiplier glued to side wall 4. cell charger pcb

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. cut here and join to 220v AC input of ionizer 2. output power to fan, insert switch in this power wire 3. case and power plug can be tossed

Image Notes 1. fan switch 2. 220V ac input 3. cell charger power board in this area

Step 9: The HV pin grid Once the cap/diode array is glued in place, then the HV pins can be placed and mounted. I used pieces of the ega tube trunking hot glued and drilled for a small cable tie. Then the fan/grid assembly is spaced (1cm) from the pin tips, and the trunking is sawed off to size. I also drilled the end caps to make them removable, 4 self tappers is all they need.

Image Notes 1. a faint glow can be seen in this 8sec exposure

Image Notes 1. where the fan grid is located for proper spacing 2. where the HV pin grid needs to be

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. marking off the fan grid position

Image Notes 1. complete, mounted glued etc 2. end cap self tappers

Image Notes 1. fan power 2. 10m ohm safety resistor 3. checking everything for proper fit

Image Notes 1. everything connected

Image Notes 1. safety resistor 2. green grid ground wire

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Step 10: The Half Wave Ionizer Start off by gluing all the capacitors, 2 rows of 15 each. This format provides voltage separation between all the HV components, better performance, safer too. Next I insulated all the connections with blobs of glue. I heard a lot of hissing when testing the unit upside down on a formica countertop, so I decided to do all the bare wires with the hot melt glue. Its quite safe seeing as nothing gets hot enough to cause the glue to go transparent let alone melt.

Image Notes 1. this side is the ac power input 2. white negative band faces ac input side

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. HV business end, take care in this area

Image Notes 1. will be soldered and snipped shorter.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Image Notes 1. blue neutral wire going to the grid 2. cheap form of insulation

Step 11: The End Cap, HV Grid and Neutral Grid A bare copper wire was formed and glued in the pvc endcap, this will be connected to the neutral wire so care should be taken to keep where fingers cant reach. Once again small pieces of pvc are used for mounting the HV CF tips.

Image Notes 1. safety resistors a must 2. CF tips mounted and hot glued 3. HV connection 4. neutral connection 5. heatshrink will be slid over this sharp solder point Image Notes 1. connection point 2. bare copper wire for the neutral grid 3. locating tabs for CF tips

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Step 12: Final Assembly The reason I dont bother with any fuses in the live leg of the AC input, is that you can get badly shocked from the HV side of things and the fuse is not even going to blow, let alone protect you. I noticed that the cap array has a tendency to rotate inside the pvc tube so I glued some locating sections inside to stop it from doing so. The important thing to remember is to discharge the unit if you want to work on it again, short the neutral grid to the HV side via the 10Meg resistors to avoid stressing any components. DON'T FORGET to short out the 220v ac input once you have pulled it out of the wall socket, the caps still carry enough of a charge to wake you up rather rudely. My future TO DO list might include: upgrading the HV pins in the full wave version to CF tips change the neutral wired grid in the half wave version to proper earth/ground grid, which just means I'll need a 3 core cable for the input instead of the present twin-flex.

Image Notes 1. neutral going down to the front cap grid 2. the fit is spot on 3. no fuses anywhere...proceed with caution

Image Notes 1. hot glued tabs to stop unit rotating inside the pipe

Image Notes 1. all wired and ready to go

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

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Comments view all 63 comments

50 comments Add Comment

petercd says:

Aug 18, 2010. 9:19 AM REPLY Yes, ozone is produced, however I'm speculating that the amount would be dependent on the working voltage. Possibly a good indicator would be the amount of corona (cute purple glow) on the pin tips, however I don't really know and am unable to give any facts concerning ozone production

rimar2000 says:

Aug 18, 2010. 3:59 PM REPLY

Thanks for the information.

t.rohner says:

Aug 20, 2010. 8:04 AM REPLY Nice instructable. I made one of these some 30 years ago. My mum wasn't that happy about it, because the high voltage charges fine dust particles and they are attracted by more or less grounded surfaces like walls and even windows ;-) If you direct the ion flow trough a grounded tube, you have a electrostatic air cleaner. (you can have a thin wire insulated in the center of the tube and connect the high voltage there. As it's done in laser printers.) You can also make a ion propulsion propeller...

wpte says:

Mar 16, 2011. 10:06 AM REPLY

I'm confused with the yellow lines... Is it wired just like the hand drawn thingy from this site: http://bigclive.com/ioniser.htm ? Also I'm having trouble finding those capacitors, I'm not even sure what the 2x suppression means :) Am I just looking for ceramic capacitors like on digikey: http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=131083 ? For the 10Mohm resistors (1/4W) what kind of film is preffered? (metal, carbon or think film) or can I pick any? :)

petercd says:

Mar 16, 2011. 11:58 AM REPLY Yes its wired like the "big clive" version, the whole thing was drawn in a cad program, so the yellow lines are the physical outlines of the capacitors,. The green lines were just to illustrate the flow of electricity in the device. Ceramic caps wont do the trick, these class x2 suppression caps, not 2 times, can be connected directly across power lines which is why they are used. Heres a link to the exact product I bought, http://www.fort777.co.za/index.php?main_page=product_info&products_id=2618 I used carbon film resistors but metal film will also do.

wpte says:

Mar 16, 2011. 12:50 PM REPLY

Cool :) so these caps: http://industrial.panasonic.com/www-cgi/jvcr13pz.cgi?E+PZ+3+ABD0029+ECQU2A104ML+7+WW would work as well? I'd like to buy things from local stores if possible, as you probably understand :)

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

petercd says:

Mar 17, 2011. 10:12 AM REPLY yep, those are good, suppression means they can be connected across a power line. The reason for me pasting the link was merely for the item description so you would have something to search for, not to buy per se, but its all good.

computerman299 says:

Mar 7, 2011. 9:00 AM REPLY

here is a little reserch that backs one of ur negative ion effect claims... Today, our modern homes and offices seal out negative ions. Computer terminals, fluorescent lighting, forced air ventilation systems, and modern building materials generate an over abundance of positive ions. Positive ions make us feel tired, depressed and irritable. http://www.peakpureair.com/negative_ions.htm (good source of info) When the amount of Negative Electric Ions contained one c.c. of air inhaled reached 5,000 to 50,000, it strengthens the body's resistance and immunity; and when the amount of Negative Electric Ions contained in one c.c. of air reached 100,000 to 500,000, it relieves illnesses. Negatively Charged Electric Ions in our body are essential in sustaining and improving our health. Whereas 85% of the Negative Electric Ions are absorbed from our skin, only 15% is inhaled and absorbed through our lungs. (quoted from page 56 of Negatively Charged electric Ion Treatment, issued by Youth Publishing)

sam.steve24 says:

Dec 23, 2010. 7:52 PM REPLY

Window AC Window AC s are the most convenient way of getting Cool.

duckythescientist says:

Sep 25, 2010. 10:31 AM REPLY I have heard about problems with operating Van de Graaff generators around computers and electronics because the ions can build up charges on the devices and fry them. My room doesn't get cleaned enough, so an ionic system like this could be a good thing for me, but I have too many electronics in my room to have them fried by something. Do you know of any research that addresses this concern?

petercd says:

Sep 26, 2010. 8:39 AM REPLY

reasearch? nope, but VdGraaf gennys build up some serious voltages, far more than these devices. The only thing that springs to mind to deal with your concerns is a Faraday shield. A tin foil lined cardboard box with the tin foil electrically grounded should do the trick.

Skyriam says:

Aug 27, 2010. 5:23 AM REPLY

So, do you know how many kV your device produces peter? Or any calculations to find out. Thanks!

petercd says:

Aug 28, 2010. 7:29 AM REPLY I built a 100M ohm and 100K ohm voltage divider to check as well as an electroscope to check the output. The electroscope is basically 2pieces of Aluminum foil hanging on a copper wire, when the ionizer is touched to the copper wire then the 2 foil pieces repel each other. So with tools in hand I first checked the Ioncare usb ionizer which was 2.65kV, the half-wave ionizer popped every diode after playing with ion propulsion so I dont know what its output is. The full wave ionizer proved a bit tricky to record a voltage level. When at first it touches the output pins I see readings of 12 to 24kV but a steady 4.2kV when I clip the voltage divider resistors to the pins. Im guessing that my 100Mohm resistors place too much load on the ionizer hence the fluctuating readings. Nice to know is that the usb ionizer uses 26.7ma (milliamp) at 5.26V DC, which works out to about 0.1399 mW which is why you cant see its power draw in the "windows usb power managment". I dont know any calculations or formula for these devices, but the usb ionizer had roughly 600V after each diode/capacitor pair, with 4 diodes and 4 caps in total giving the 2600kV output....for what its worth.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

duckythescientist says:

Sep 25, 2010. 10:08 AM REPLY Here is a link to a website explaining the math behind the CW multiplier. There is a link at the bottom of the page for a calculator that will do the equations for you, but it wasn't working today when I checked. It has worked in the past, so it might work later. http://www.blazelabs.com/e-exp15.asp

8v92 says:

Sep 12, 2010. 8:22 PM REPLY Good componet layout , It would supply more output current if ground was replaced with neutral on center terminal and live was connect to both outside terminals so you have two crockoft walton voltage multiplers in parralel. At 220 vac output voltage is around 4750 volts DC . With 30 capacitors a 15 stage unit (single multi[pler) could be built that would put out 7250 volts DC. Also all capacitors after the first stage diode have at least 500 volts DC acrross them but the type of capacitor used can take some overvoltage. With a few changes this unit could also remove smoke and dust from the air (electrostatic precipitater).

petercd says:

Sep 13, 2010. 12:49 AM REPLY

sweet, thanks for the heads-up. Dust removal was also a priority, but negating the ozone produced would be a concern. I suppose the easiest would be to leave it on in the day when I'm at work and simply switch it off when I come home again.

8v92 says:

Sep 13, 2010. 9:03 PM REPLY Whenever a conductor with sharp point/s with a high voltage potential of one polarity is near a conductor of opposite polarity ionization and corona discharge occur that produces the o3 molecule or ozone. If you smell an earthy plowed field oder near high voltage equipment that is ozone. In an electrostatic presipitater air flows through a metal screen connected to ground or in this case + to remove any negative --- charge on the dust so it will be attracted to and stick to a wire several inches away from the screen that has a negative charge on it (opposite charges attract) because the screen and wire are not close there is little or no ozone produced.

CyborgGold says:

Aug 24, 2010. 10:07 PM REPLY

What wattage shoudl the resistors be, I searched online and found them in 1/2W, 1W, and 2W

petercd says:

Aug 25, 2010. 1:01 AM REPLY 1/4 W is fine, so 1/2W is more than adequate. The current consumption is extremely small working out to about 2mW in the usb version and around 5~10mW in these versions. The brushless fan consumes 89mW and is the major current draw in this device.

CyborgGold says:

Aug 27, 2010. 1:03 PM REPLY

Thanks for the help!

Plasmana says:

Aug 19, 2010. 5:49 PM REPLY I may be wrong (and no offense!) but I think your design is flawed. By having an grounded fan guard in front of the HV output, it will take out all the negative ions we need, only blowing out ozone (O3) which is not what we want. In all commercial products I have taken apart has NO grounded metal piece to encourage ions from the HV pins. It is just HV pins sticking out into the air, sometimes assisted by a fan. A nice project though! (it encourages me to make me one too, lol)

petercd says:

Aug 22, 2010. 5:02 AM REPLY

It was just in my testing by feeling the ion wind that led me to add the ground grid. Most of my info came from the http://www.bigclive.com/ioniser.htm site. However, I bumped into a commercial product from 3M in my web travels, taken from the 3M 960 instruction manual : "To reduce the risk of electric shock, the 960X/980X uses a grounding plug that has a third (grounding) pin. This plug will only ﬕt into a grounding-type power outlet. If the plug does not ﬕt into the outlet, contact qualiﬕed personnel to install the proper outlet. Do not alter the plug in any way." Im betting that this units' grids are definitely grounded to prevent operator harm. thanks for the input all the same.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Treknology says:

Aug 19, 2010. 10:36 AM REPLY The carbon fiber is a brilliant idea. I remain concerned about the Earth being used as part of the circuit. If your house is wired properly, there should be no measurable voltage between Neutral and Earth--if there is, something is seriously amiss. The Earth is there for safety, any current leakage to earth should trigger a breaker on your switchboard, even as minute as generated in this device. It also means that if this device continues to function while plugged in, then any metal/earthed appliance in your house could also bite.

petercd says:

Aug 20, 2010. 11:08 AM REPLY I took apart my outside electrical box to check how things are wired before the cable enters the house, in other words straight from the power company before my indoor distribution board. The black neutral is clamped to the armour sheath of the power cable and the green earth/ground wire from the outdoor ground spike. There is no voltage between earth and neutral as you rightly point out, however with my device connected indoors, no voltages are measured between the now disconnected ground spike and "house earth" nor does my earth leakage trip. Im guessing its because there is no current flow only ion flow. If for some reason the ground becomes isolated from the physical ground spike of even the electrically connected neutral, then a dangerous condition could exist whereby you could receive a nasty shock from the now live floating ground.

Skyriam says:

Aug 19, 2010. 3:12 PM REPLY He's using the earth wire just to attract negative ions to it and make it easier to distribute them, no current is going to it. You can make it without the earth attraction.

Treknology says:

Aug 19, 2010. 5:01 PM REPLY If you look closely at the wiring of the "full wave" version, the connections are Active to Earth and Neutral to Earth. Safety is paramount in these sorts of projects, and I recommended elsewhere that a full-wave bridge rectifier be used across Active and Neutral with the "half wave" voltage muliplier. Using the Earth as a collector plate is not an issue. Having the Earth connected into the voltage multiplier IS an issue.

Skyriam says:

Aug 19, 2010. 6:10 PM REPLY

You're right, thought about the half wave version. So how do you make it full wave without earth connection?

Treknology says:

Aug 19, 2010. 10:52 PM REPLY Using the voltage multiplier directly from the AC is dumping half of every "wave" cycle. Use a full-wave bridge rectifier (the four diodes arranged in a square) so that both waves are flipped to the "same side" and then use the "half wave" version of the multiplier to process what is now a "double" half wave, i.e., unregulated DC. My father was an electrical inspector and safety officer--I grew up connecting 240V cable before I could do long-division, so SAFETY is always foremost on my mind.

Skyriam says:

Aug 19, 2010. 3:22 PM REPLY Nice instructable! You beat me to it, I was making one about this too haha, one question though: Do you know how many kV does this produce? I've read a lot on the subject and found out that about 6kV to 8kV should do the trick without producing much ozone, anything higher would produce lots of ozone, some guy even woke up in the morning with headache because of this (he kept it running all night), he found a way to regulate the input voltage from the AC line (reduced it at night) but I can't tell how and I don't seem to find the calculations/theory for this anywhere to math my way in it and find out how many kV per stage. Hope you can help me, cheers! Take care.

Treknology says:

Aug 19, 2010. 5:05 PM REPLY

Most commercial units only operate at about 1.5 kV.

Skyriam says:

Aug 19, 2010. 6:08 PM REPLY

I don't think that's correct. For the corona effect to take place you need at least 4kV.

Treknology says:

Aug 19, 2010. 9:52 PM REPLY It depends on how sharp the needles are or how thin the wire is. Most laser printers and photocopiers user corona wires to charge paper and drum and 4kV in that cramped space wouldn't go down too well. If you want a visible corona, then yes, you want a higher voltage, but you can feel a gentle "corona wind" from only 1.5kV. Serious NIG vendors supply replacement needles because the originals will go blunt as the metal is gradually discharged along with the negative ions. A unit that is entirely closed with inbuilt filtration could well operate at a higher voltage.

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

lucek says:

Aug 19, 2010. 7:07 AM REPLY WARNING! Devices like this have produced O3 aka Ozone. This has shown to aggravate breathing conditions like asthma. DO NOT repeat DO NOT use ionic cleaners if you or someone in the residence has breathing conditions. Further there is some risk of developing breathing conditions including but not limited to lung cancer. http://www.epa.gov/iaq/pubs/ozonegen.html

Thoth says:

Aug 19, 2010. 8:34 AM REPLY A way too avoid or minimize the the dangers associated with breathing ozone, is simply to run the device while no one is in the room and turn it off before the room is to be occupied, it has a short half-life.

lucek says:

Aug 19, 2010. 2:01 PM REPLY

or just not to use them at all.

Skyriam says:

Aug 19, 2010. 3:10 PM REPLY Don't get in a car, you may die. Don't go out while raining, you can get struck by lightning... twice. Come on man, the benefits are greater than the risks, besides ozone is very easy to detect, its smell is very strong and if you don't smell it then its far too small to cause any harm. Chill.

lucek says:

Aug 19, 2010. 4:18 PM REPLY There is a question of risk vs. benefit. The risk is real. The benefit is minor. you receive less dust in the air but the same results can be had with a simple filter. if you argue that the ionic air purifiers work better (witch isn't proven) I'll point that only people with severe respiratory problems need that purity of air and they are the most susceptible to Ozone. BTW the safety levels are set at 0.05 ppm by the FDA far less then is noticeable. OSHA sets the safety level at twice that over 8 hours but still to small to smell.

Skyriam says:

Aug 19, 2010. 6:13 PM REPLY There's more ozone/negative ions in the sea, forest and mountain environments than this little thing produces. So if you live near any of this places do you get sick from ozone? NO.

lucek says:

Aug 19, 2010. 8:35 PM REPLY Materialistic fallacy doesn't work sorry. Again I listed safety levels. We have no tests of this device so we can't judge it's safety or ones built on it's design. Until it is tested we should assume it can be dangerous and the same should go for every one built on the design. When it comes to O3 "good up high - bad nearby".

typenamehere_____ says:

Aug 19, 2010. 7:21 PM REPLY *THE REPLY BUTTON IS MISSING FROM THIS PAGE ALTOGETHER, NOT SURE WHY* @petercd & rimar2000, 2 comments down, at reply that says 9:19 AM. You are correct in your speculation; ozone is caused by corona discharge. Why? Ozone occurs when oxygen molecules (O2) are broken down and the sole atoms connect to other O2 molecules, forming O3. Often, this is caused by ultraviolet light being absorbed by the atoms. When there is a voltage high enough to pass the breaking point of the air, an electric spark occurs, which is visible because it releases a wide range of different electromagnetic waves (A.K.A. "normal" light, microwaves, radio waves, ect.), one of these being ultraviolet. So, the higher the voltage between two points, the higher the chance of corona discharge, the higher the chance of significant ozone production. However, if you only have a negative charge and a very well distanced positive charge, you have little to worry about (until, of course, you start up your VanDeGraaff machine...)

twighahn says:

Aug 19, 2010. 2:22 PM REPLY

do u know how to make an ion humidifier?

-max- says:

Aug 19, 2010. 1:47 PM REPLY

instead of using a big voltage multiplier, can i use a NST? withl AC to DC converter?

Pleasetrustme says:

Aug 19, 2010. 1:02 PM REPLY There is nothing dangerous about these devices.I have one on as I write this and I sleep soundly. "May cause complications for asthmatics" Yeah and the dust it removes does too. Anything that is not endorsed by university or government study is given fraud status. You all should call your friend and stick that mini microwave against your brain and tell him these things are dangerous. Afterword's get up off your lazy butts and microwave some fake manufactured food in the machine that is fry your whole body. Don't get in a vehicle you may die.Don't walk or ride a bicycle you may fall down. Learn how the American team defeated the Soviet Hockey team a the Lake Placid Winter Olympics. They put positive ion generators in the Soviets practice areas and dressing rooms and had negative ion generators in the USA practice areas and dressing room. Who won? These devices should be used extensively. The risks are minimal.

tongpu says:

Aug 19, 2010. 12:33 PM REPLY

Just wondering. How often, what parts & how do you clean them safely?

gnume says: any idea what modifications are needed for those to work at 220 ~ 230 V electrical system ?

http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Aug 19, 2010. 9:35 AM REPLY

petercd says:

Aug 19, 2010. 12:00 PM REPLY

I live in South Africa where we use the 220V system, actually 239V AC so basically no mods needed.

gnume says:

Aug 19, 2010. 12:24 PM REPLY thanks on the info i live in israel so my voltage some times jumps from 220 V to a max of 240 V so here it a good idea to over build the systems a bit

Treknology says:

Aug 19, 2010. 10:25 AM REPLY This approach is NOT recommended in Australia! The connection to Earth should trigger a Leakage Breaker immediately the device is plugged in. One is recommended to use a standard full wave rectifier and then use that out put to drive the "half wave" version of the circuit.

Treknology says:

Aug 19, 2010. 10:19 AM REPLY @Rimar2000: Yes, all Negative Ion Generators produce Ozone. The Ozone output increase with the voltage output. It is dedectable by the "electric coppery" smell emanating from the unit. The limiting resistors in the circuit do not lower the output voltage, they are there to reduce current output so that people don't electrocute themselves on the pins. The actual voltage is controlled by the number of Capacitor/Diodes. Reducing their number reduces the voltage. Ozone is itself useful, but in this case the more that escapes from the unit, the blacker your walls will be come as all the dirt you would otherwise be breathing in will adhere to the walls. Because this design includes a neutral plate, there is somewhere for ions and ozone to be captured which would reduce this problem. Electrostatic filters use the same approach: highly charged air is sucked into through neutral plates to capture the dirt and ensure that uncharged clean air is output at the other end. It is also NOT recommended to use such a device near a computer--static discharge may go un-noticed by you, but not the computer!

ARJOON says: i need a vid nice and clean work dude

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http://www.instructables.com/id/How-to-Make-a-Negative-Ion-air-ionizer/

Aug 19, 2010. 10:02 AM REPLY