Warning to anyone with Cree headlamps
#26
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It's almost comical that they closed down a stall because they were selling cheap chargers. In the US anyway, cheap chargers are the NORM in the aftermarket - so much so that it's almost difficult to find a GOOD charger. Even if you go to Amazon and look for name brands, you are still likely to get a cheap knockoff.
I finally had to give up on my Belkin boycott which I've had going for > 10 years and use Belkin - at least for cables and chargers, I still won't buy their routers.
I finally had to give up on my Belkin boycott which I've had going for > 10 years and use Belkin - at least for cables and chargers, I still won't buy their routers.
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#27
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It's almost comical that they closed down a stall because they were selling cheap chargers. In the US anyway, cheap chargers are the NORM in the aftermarket - so much so that it's almost difficult to find a GOOD charger. Even if you go to Amazon and look for name brands, you are still likely to get a cheap knockoff....
#28
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Not really. The charger simply shorted the 220v mains to the ground side of the USB connector. This made the case of the iPod and also the headsets live. All she needed to do then was to touch something that was grounded, which was apparently the metal case of her laptop. It's actually not improbable, if you've ever seen the inside of those ****ty chargers, it's surprising it doesn't happen more often.
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#30
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From: Bay Area, Calif.
The first part is easy to understand, but I'm surprised that any exterior part of the phone or headset would be metal that's electrically connected to the USB power pins (either ground or live). I always have my phone in a protective rubber case anyway but safe electrical design would call for the metal parts of the case to be insulated from electrical power.
#31
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I don't think they were connected to the power pins, I think it was connected to the shell. it's pretty normal for the shell of a connector to be electrically connected to the shell of the unit and also possibly to the common ring on the headphones. It's normal design to connect all the earth connections together, but when your source for "earth" is broken and attaches the "earth" to a 220v main, things get ugly.
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#33
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Doesn't take very much at 220v to kill a person. A small fraction on an amp. Also, it's going to be an EXTREMELY slow blowing fuse. The wire is going to heat up and burn the insulation off and smoke for many seconds before it actually breaks, even if it's carrying a couple hundred ma at 220.
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#34
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From: Columbia, Maryland
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Hey, whatever. I charge my phone on a plug-in wall charger. Writing on the charger says it's rated for between 100 and 240 volts. To me it looks like a small plastic box with a plug on it that weighs a couple ounces. Written on back are the words, "Made in China". I bought it at Radio Shack for maybe $24. I plug it in every night before I go to bed and I sleep like a baby. Riding my bike on the road; now that will give me the heebie-jeebies. Now if I start hearing about more people turning to toast while using a plug in charger I'll have to rethink that opinion.
#35
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From: Michigan
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Hey, whatever. I charge my phone on a plug-in wall charger. Writing on the charger says it's rated for between 100 and 240 volts. To me it looks like a small plastic box with a plug on it that weighs a couple ounces. Written on back are the words, "Made in China". I bought it at Radio Shack for maybe $24. I plug it in every night before I go to bed and I sleep like a baby. Riding my bike on the road; now that will give me the heebie-jeebies. Now if I start hearing about more people turning to toast while using a plug in charger I'll have to rethink that opinion.
I actually threw away the chargers I bought on ebay after seeing a teardown of one on YouTube. I paid $1.87 each for them. They worked pretty well but the inside of them is scary - really bad components, no proper isolation routing or anything like that. It looks EXACTLY like an Apple charger on the outside, but the inside of the Apple charger is actually very well designed.
For some things, it's not a big deal. I buy MicroUSB cables 5 for $10 on eBay and don't worry about it. Worst they can do is to short out or the end break off, neither are deadly hazards. Anything that connects to the mains though, lately I've stuck to name brands purchased through reputable channels. Simply "name brand" doesn't work anymore, since the product copiers are EXTREMELY good at making products indistinguishable from the real thing.
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#37
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From: Michigan
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Every cheap clone that I've bought has had UL and CE logos on them. They are not, of course, UL or CE listed/approved. The clone makers do not care, they will print anything on the device that helps sales.
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#38
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From: Seattle
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Ken Shirriff's Blogs on this topic have been often cited, and quite interesting. Compares some cheap clones to real (Apple) chargers, and the safety issues. He has several blog articles on chargers, but here is a start:
Ken Shirriff's blog: iPad charger teardown: inside Apple's charger and a risky phony
Ken Shirriff's blog: Tiny, cheap, and dangerous: Inside a (fake) iPhone charger
Ken Shirriff's blog: Apple iPhone charger teardown: quality in a tiny expensive package
IMO, battery chargers for other devices such as lights are another whole wild west. You can never really tell about the quality of these device specific chargers, and the specs are often cloudy if you want a replacement. My original Magicshine charger has some LED indicating a charge/stop charge function, and some units have been known to burn up.
Chargers for specific cells such as 18650 LiIon are a little better if you do research such as on Candlepower Forums.
Danger is certainly there; I decided to never charge batteries when I'm not there. It's amazing to me that more fires and so on aren't seen.
Ken Shirriff's blog: iPad charger teardown: inside Apple's charger and a risky phony
Ken Shirriff's blog: Tiny, cheap, and dangerous: Inside a (fake) iPhone charger
Ken Shirriff's blog: Apple iPhone charger teardown: quality in a tiny expensive package
IMO, battery chargers for other devices such as lights are another whole wild west. You can never really tell about the quality of these device specific chargers, and the specs are often cloudy if you want a replacement. My original Magicshine charger has some LED indicating a charge/stop charge function, and some units have been known to burn up.
Chargers for specific cells such as 18650 LiIon are a little better if you do research such as on Candlepower Forums.
Danger is certainly there; I decided to never charge batteries when I'm not there. It's amazing to me that more fires and so on aren't seen.
#39
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From: Columbia, Maryland
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Regardless, these things are cheap and mass produced with likely little to no quality control. I think it's in my best interest to unplug it when I leave the house. I might also rethink using it while I sleep although I've never had any problems with it. My reasons for doing a 180° flip-flop, simple; I don't trust cheap battery chargers for charging my bike batteries while unattended so why should I trust these cheap phone chargers? Oh I still plan on using them but I'll be home and wide awake when I do. In the mean time I might see if I can find a plug-in circuit breaker/Surge protector to use with the phone charger just to keep things a little more safe.
...now if they make a UL listed phone charger with built in 1A circuit breaker I'd like to get me one of those.
#40
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From: Garner, NC 27529
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Doesn't take very much at 220v to kill a person. A small fraction on an amp. Also, it's going to be an EXTREMELY slow blowing fuse. The wire is going to heat up and burn the insulation off and smoke for many seconds before it actually breaks, even if it's carrying a couple hundred ma at 220.
Personally, I'll do anything with 110.
But ever since I saw 220 blow a sizable hole in 1/4 stainless on a stove... I wouldn't touch it.
Still figured that the cable would vaporize nearly instantly.
#41
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It's current that's going to vaporize the cable. Since it's going through a human body, it's hitting a resistance of at least a thousand ohms even if the person is sweaty and it's a direct skin to metal contact across a small piece of their body.
Assuming worst case 1,000 ohms and 220v, that's 220/10000 = 220 milliamps. The wire will probably carry that indefinitely. A very thin wire would get pretty warm, but i doubt it would actually melt in two. At 220v that's only 220*.22 = 48 watts.
Note that at 110v, you'd still be dead. 110ma at 110 volts is MORE than enough to stop your heart. Though of course assuming the same design on the charger it would be half as likely to jump an identical air gap in the first place. If you got the thing wet though it would fail the same either way.
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#42
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From: Garner, NC 27529
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You should never leave the US then. Japan is maybe OK. Pretty much the rest of the world uses 220v as their standard mains outlet.
It's current that's going to vaporize the cable. Since it's going through a human body, it's hitting a resistance of at least a thousand ohms even if the person is sweaty and it's a direct skin to metal contact across a small piece of their body.
Assuming worst case 1,000 ohms and 220v, that's 220/10000 = 220 milliamps. The wire will probably carry that indefinitely. A very thin wire would get pretty warm, but i doubt it would actually melt in two. At 220v that's only 220*.22 = 48 watts.
Note that at 110v, you'd still be dead. 110ma at 110 volts is MORE than enough to stop your heart. Though of course assuming the same design on the charger it would be half as likely to jump an identical air gap in the first place. If you got the thing wet though it would fail the same either way.
It's current that's going to vaporize the cable. Since it's going through a human body, it's hitting a resistance of at least a thousand ohms even if the person is sweaty and it's a direct skin to metal contact across a small piece of their body.
Assuming worst case 1,000 ohms and 220v, that's 220/10000 = 220 milliamps. The wire will probably carry that indefinitely. A very thin wire would get pretty warm, but i doubt it would actually melt in two. At 220v that's only 220*.22 = 48 watts.
Note that at 110v, you'd still be dead. 110ma at 110 volts is MORE than enough to stop your heart. Though of course assuming the same design on the charger it would be half as likely to jump an identical air gap in the first place. If you got the thing wet though it would fail the same either way.
many times.
Fixing wiring around various houses, garages, and student slums when I was in college.
Sometimes it hurt, occasionally it hurt a lot.
I guess I still got lucky.
#43
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The key is which part of your body takes the hit. As long as it doesn't go through your chest or directly across your brain, you're probably going to be fine.
I once read of a lineman who took a hit from one arm to the other directly off multi thousand volt neighborhood feeds, having it cook both of his arms (both had to be amputated) but for some reason the current went through his pectoral muscles instead of through his heart, and he lived to become a safety lecturer for the company.
A small fraction of that could kill you if the current goes a different way. Your body position, chemistry, what you're wearing, etc could all change it.
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