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After a User Dies, Apple Warns Against Counterfeit Chargers
After a Chinese woman was earlier this month evidently electrocuted while talking on her iPhone while it was plugged in to charge, Apple is warning users to avoid counterfeit chargers. From CNet:
"Last week, reports surfaced in China that suggested the woman, Ma Ailun, might have been using a third-party charger designed to look like the real thing. Although third-party chargers are not uncommon, they vary widely in terms of safety and quality.
Earlier this year, safety consulting and certification company UL issued a warning that counterfeit Apple USB chargers were making the rounds and that consumers should be on the lookout for them due to their lower quality and possibly dangerous defects. The company posted the guidance on its site after a woman was allegedly electrocuted while answering a call on her iPhone."
Whether or not the counterfeit charger was the cause, they have reinforced their image and promoted their chargers (as well as discouraging customers from buying their chargers elsewhere).
There are lots of "third-party" Android chargers out there -- ordinary MicroUSB things. If "counterfeit" (i.e. non-Samsung, or whatever) chargers were a problem, wouldn't this happen all the time with Androids?
Sounds like Apple is just taking advantage of the opportunity to scare people into paying the Apple Tax.
When I finally dumped my iPhone 3G, it was because it kept shocking me every time it rang. I don't know about the iPhone 5, but I think blaming the charger might be a little simplistic given that experience.
In SOVIET RUSSIA... erm...NSA AMERICA, the Internet logs onto YOU!
Those wires can easily carry 1A which at 220V is more than enough to kill you. The exposed metal bits of a device are often connected to a shield ground, and if that "ground" is actually at 220V line potential then it would be easy to kill someone.
No one is being killed by the 5v on the USB bus. The problem is the counterfeit chargers are often poorly designed and can fail in a way that shorts the USB cable to the AC power.
There was an excellent teardown & analysis of a cheap charger last year that pointed out serious safety issues.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
Take a look at a teardown of a fake charger and you'll understand why it can be lethal. The creepage distances in particular are atrocious.
No one is going to die by having 5volts applied to their face.
But they do die from having 220 volts applied to their face.
The issue is that the counterfeit chargers short and deliver the mains directly to the head. It doesn't matter what electronic device is involved. hell, doesn't matter if any electronic device is connected to the end of the other side of the USB cable when the circuit is completed.
See the commentary at the top of the page from this link:
http://www.righto.com/2012/03/inside-cheap-phone-charger-and-why-you.html
--Paul
I'm not buying it, how could you possibly screwup a USB charger to the point where it would be lethal? I mean the cables aren't generally thick enough to carry enough 220V current to kill someone before they melt and 5.5V DC certainly isn't going to kill someone.
It only takes 100mA - 200mA of current to kill someone, and every USB cable is designed to carry at least 500mA since the USB spec says that USB hosts can supply up to 500mA of current (and many plug-in chargers exceed that). So it's certainly feasible that a USB cable can carry enough current to kill someone. It's not the voltage the determines the size of the conductor, it's the current.
The USB cable wires may not have sufficient insulation to protect against 220VAC (peak voltage is higher, around 310V if I remember correctly), but that's the point -- 220VAC is not supposed to be supplied to a USB device. But even if it's not certified for the voltage it seems that the individual conductor insulation combined with the plastic outer sleeve of the USB cable would seem to provide at least enough isolation, I think most plastics used for insulation have around 500 - 1000V/mil (1/1000th of an inch) of breakdown voltage.
I'm surprised that a phone doesn't have at least 220VAC of isolation between the USB power and the phone case. Is this typical in phones?
Are you saying that China has counterfeit electronics? And that they don't meet safety standards? This simply must be a joke.
Current shmurrent. She died because she wasn't holding it right.
The new "lighting" connector is very solid and handy, contrary to micro USB.
Its designed that way for obvious reasons.
http://en.wikipedia.org/wiki/USB#Mini_and_Micro_connectors
"The Micro plug design is rated for at least 10,000 connect-disconnect cycles—significantly more than the Mini plug design.[38] It is also designed to reduce the mechanical wear on the device; instead the easier-to-replace cable is designed to bear the mechanical wear of connection and disconnection"
The cheap adapter may have sent big voltage to the phone connecteor... But IT'S THE APPLE DESIGN that bring that voltage outside the phone...
If the two leads of the charger are (relative to ground) 220V and (220+5)V, the phone should charge just fine and the user would still be fine...
If the charger send a rogue voltage (like 0V and 220V), the phone internals should get fried... but the user should still be fine...
But some retard thought it'd be cool to use the metal frame of the phone as an antenna... This lead to the "antenna-gate" with people losing their phone signal when holding the phone the wrong way, but that part is more funny than other. But this also mean that any invalid voltage sent to the phone connector may also reach that metallic frame and the user... With the sad consequences that you've seen here !!!
When you see electrical recommendation for electric appliances, you see that the box of an electric device should be grounded or completely insulated... Apple failed that basic recommendation... and THEY are responsible for that part.
Any phone charger can go rogue... this is even true for Apple's "official" chargers (even if risks are lower).
, and they contain a bit more than a simple transformer and regulator.
They take the AC line voltage, rectify it to high voltage DC, chop the DC up into high frequency pulses with a MOSFET, step the pulsed voltage down with a specially designed transformer, then rectify the output to low voltage DC. A sample of the output DC is then fed back to the primary side circuitry to achieve closed loop regulation.
Because the primary side of the system is at line potential, the insulation in the switching transformer (and the optocoupler used in the feedback loop) is all that prevents the output side from presenting a shock hazard with respect to earth ground. The quality of construction of many of the Chinese knockoff chargers is downright terrible, and I could easily believe that an insulation breakdown. Dave Jones "EEVBlog" did a teardown of one of these a while back. Scary stuff if you know what you are looking at:
http://www.youtube.com/watch?v=wi-b9k-0KfE
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Do you really think that counterfeiters would suddenly go legit if the process was easier? Counterfeiters will fake anything they think will make money. For goodness sake, they counterfeited toothpaste. They don't care if their fakes are functional or safe as long as they pass a cursory inspection to the real thing.
Well, there's spam egg sausage and spam, that's not got much spam in it.