Purely Snake Oil? - Page 1
Forum section: electronics / general

author: orion242
author_rank: Unknown
timestamp: February 11, 2014, 01:03:53 am
content: So the other night I notice a new LED night light in our bed room. I ignored it, nothing special and it was late. Well the wife asks if I noticed our new negative ion generator night light. Sure, its hard to miss a light in the otherwise dark room. She proceeds to pitch me what sounded like a late night infomercial praising negative ions while my bullshit alarm is going off.It finally ends with her asking if I can disable the annoying light and keep the ion generator. Sure can! I would love to break that thing open to see what is going on.So this is the producthttp://www.purelyproducts.com/Products/ProductDetail/tabid/77/ProductID/7/Default.aspxTake it down to the lab and first thing that strikes me, no UL, CE or other safety mark. There are also two 1/4" holes in the back that I can see the PCB and solder joints which seems a bit odd. Take out the screws and dear god, it looks like someone pulled it out of their rear... The PCB and all the components are covered in some sticky residue... Just a quick glance at the circuit and the all the health benefits seem to emanate from a single one-hung-lo component with a .cn website clearly marked. This guy has a 1ohm resistor in series with it, straight across the mains. Huh, lets take a look.http://www.comwell.com.cn/en/prod_show.asp?id=174Regardless my expectations for this quick little teardown were super low, and well, I wasn't disappointed. Now I have to explain to the wife that I would not rather die in the house fire when this POS decides to self-destruct in the middle of the night.They even recommend this thing for children's bedrooms...So am I expecting too much or is this the state of consumer products? Your thoughts on this negative ion voodoo?

author: dr.diesel
author_rank: Super Contributor
timestamp: February 11, 2014, 01:09:50 am
content: When my wife buys plug-in air fresheners, I unplug them and toss them in the trash, quietly.It's a game, we go through lots of air fresheners.

author: Tinkerer
author_rank: Frequent Contributor
timestamp: February 11, 2014, 03:08:08 am
content: Well, seems like they went nuts with the flux. Didnt bother cleaning it or made sure it was exposed to heat to harden it.As for the ions. Seems like it would increase static charge in the air. Where as positively charged ions are recommended as a way to counter ESD.Maybe you could detect ghosts with this? haha

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 11, 2014, 06:01:33 am
content: A similar module is found in one of those Sharper Image bathroom air cleaners. (I got one for crazy cheap at a garage sale a few years ago.) It draws very little current and will run happily with a 0.1uF X2 cap in series with it. The cap would limit fault current should it fail shorted.

author: amyk
author_rank: Super Contributor
timestamp: February 11, 2014, 08:56:00 am
content: Apparentlythey do have some efficacy...

author: JuKu
author_rank: Frequent Contributor
timestamp: February 11, 2014, 09:50:26 am
content: Seems to work, you got lots of negativity out of it.

author: jwm
author_rank: Regular Contributor
timestamp: February 11, 2014, 12:18:44 pm
content: I do feel extremely energized before a storm, I don't know if it has anything to do with negative ions, just some part of my vestigial lizard-brain giving me an indistinct urge to find a cave to build a fire inside of for the night. Certainly ion generators have never had the same effect.It is a handy and cheap 3-6kv DC power supply though. Build an electrostatic motor, I always thought that was a pretty cool science experiment/demo.

author: cybermaus
author_rank: Frequent Contributor
timestamp: February 11, 2014, 12:50:47 pm
content: Ion generation?First I heard of that was when Laser printers started to appear, and their ions were Ozone which was supposed to bebadfor you. So I never did understand these devices. Maybe its a 'different type' of ions, but it has to come out of air, and is generated by high voltage, so I am pretty sure Ozone is formed even if only a side product. Either that, or carbon or hydrogen or nitrogen ions, and I never heard of those in combination with HV static.Maybe show this to your wife:http://www.austinpureair.com/index.php?option=com_content&view=article&id=92:ozone-a-dangerous-pollutant-not-an-air-pollution-cure-all&Itemid=9Maybe its best if the device really is all show, and does not actually do anything at all. Maybe just disconnect the HV part, leave the LED's on.

author: madires
author_rank: Super Contributor
timestamp: February 11, 2014, 01:30:20 pm
content: Quote from: dr.diesel on February 11, 2014, 01:09:50 amNo tear downs? I'm disappointed

author: dr.diesel
author_rank: Super Contributor
timestamp: February 11, 2014, 01:33:22 pm
content: Quote from: madires on February 11, 2014, 01:30:20 pmI've just recently started a new trick. Instead of trashing them, which she easily notices they are gone, I've clipped off the hot prong! Now they don't heat, therefor don't stink up the house, she has yet to catch on.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 11, 2014, 03:15:15 pm
content: Quote from: cybermaus on February 11, 2014, 12:50:47 pmNegative ion generators and ozone generators are not the same thing. The process of generating negative ions creates some ozone, but a well designed negative ion generator should not generate much ozone. There are some that even have a catalyst to neutralize the ozone that is produced. The key is a very low current and a large ion emitting area.I suppose something to try is to just gut the whole thing (saving the parts) and see if it works by "placebo effect".

author: orion242
author_rank: Unknown
timestamp: February 11, 2014, 03:33:33 pm
content: Quote from: NiHaoMike on February 11, 2014, 03:15:15 pmI was thinking the same thing. Saving the parts I'm on the fence, normally I would. But they are all ,as Dave would say...CRUSTY!!Maybe I should send Dave one. It's mood improving ions would help calm him down after the fake USB connector video

author: G7PSK
author_rank: Super Contributor
timestamp: February 11, 2014, 04:06:18 pm
content: My wife bought a hair dryer with an ion generator built in, supposed to be good for the hair, you can turn it on and off with a switch which lights a blue led when its on, I took the thing down in order to find out what it did, the led was driven from a tapping on the heater element, nothing else just the led.I read somewhere that ions will turn into ozone eventually if not discharged before hand and ozone is not good.

author: N2IXK
author_rank: Frequent Contributor
timestamp: February 11, 2014, 10:53:26 pm
content: Back in the 80's, I had a job as a bench tech at a repair shop, and we had a customer who would be bringing her VCRs, tape decks, answering machines in all the time for mechanical issues like broken belts, dried out pinch rollers, cracked idler tires, etc. LOTS of seriously dried and deteriorated rubber. Turns out she was a BIG believer in those negative ion generators, which apparently were pumping out a non-trivial amount of ozone.She refused to believe that they were the cause of the problem, until we gave her an extra brand new belt, and had her drape it over one of the units as a test. It crumbled to dust when she went to check it a month later. I have to wonder what all that ozone was doing to her lungs...

author: smashedProton
author_rank: Frequent Contributor
timestamp: February 11, 2014, 11:08:29 pm
content: You forgot the option on the poll where they are unhealthy to breathe the air but they work. I sometimes run my old plasma speaker project to knock everything in the air down before I work on sensitive equipment. I'm just sure to not go into the room for 30 minutes after I turn it off.

author: mariush
author_rank: Super Contributor
timestamp: February 12, 2014, 12:12:19 am
content: Here's an ozone generator:Here's an ionizer / negative voltage generator .. with 11 stage multiplier to do high voltage, like Dave showed in a video (longer video, with some explanations) :

author: Tinkerer
author_rank: Frequent Contributor
timestamp: February 12, 2014, 12:20:23 am
content: Indeed, ozone is bad to breath in when in any significant quantities. Its supposed to abrade your lungs or something like that as well as cause irritation in the short term. I have heard of ozone being used for health benefits or something before, but use like that is supposed to be a more targeted approach and not just fill the room with it.It is really easy to create ozone using high voltages.

author: edavid
author_rank: Super Contributor
timestamp: February 12, 2014, 12:24:21 am
content: If you read the spec the OP provided for the ion generator, it says "Remainder O3< 0.02ppm". The US NAAQS 8 hour standard is 0.075ppm, so if you believe the (vague) spec, there's no problem.

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 12, 2014, 02:05:24 am
content: Quote from: edavid on February 12, 2014, 12:24:21 amIt's so low powered that the ozone generation would be minimal, as in too low to smell. About 0.01ppm is the "smell point" for ozone. To further decrease possible ozone production, increase the ion emitting area. (e.g. use a loop of thin wire instead of a needle.)

author: cybermaus
author_rank: Frequent Contributor
timestamp: February 12, 2014, 08:01:49 am
content: Quote from: NiHaoMike on February 12, 2014, 02:05:24 amChanges are mine not Mike's.You can also simply not plug it in. Or not buy it.

author: amyk
author_rank: Super Contributor
timestamp: February 12, 2014, 12:23:14 pm
content: Quote from: Tinkerer on February 12, 2014, 12:20:23 amOzone is used to sterilise things by killing anything living on them. It works very well for this.