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physicsprof

macrumors member
Jun 24, 2010
46
37
Chicago, IL
This is why we should all use 30V DC electricity, instead of 120V and for crap's sake 220V???

It seems you're surprised that we use "high" voltages, and AC instead of DC. Maybe it would help to brush up some high-school physics before making suggestions?

First, higher voltages are FAR more efficient in transmission. Also, even within the house you would end up with very high currents for your appliances. en.wikipedia.org/wiki/Electric_power_transmission

Second, you suggest to use DC instead of AC. In fact, that discussion dates back to the early days of our electric grids; en.wikipedia.org/wiki/War_of_Currents might be instructive.
 

shiekh

macrumors member
Sep 26, 2006
83
13
In any case, stuff like this makes me glad I live in a country where we only have 120V household AC instead of 200V+. Might be a little less efficient for heavy appliances and waste a lot of copper in the walls, but WAY safer. Not that 120V can't kill you too, but it's a whole lot less likely, and from what I've heard from people who've been hit by both (I've fortunately never felt more than 120), 240V will leave you feeling much, much worse.

Actually most US houses have both, the higher voltage for the range/dryer and the lower voltage for other stuff.
 

Renzatic

Suspended
At very large voltages.

We should all just say it requires a bunch of things. Voltage by itself is harmless. A static discharge can be as high as 20,000 volts, but has almost no amperage. But for all those milliamps to kill you, you need voltage to pass through your skins natural resistance to electricity.

I think the safest thing to say is that only Big-TDI-Guy looks like he knows what he's talking about in this thread.
 

nec207

macrumors 6502
Mar 21, 2011
429
0
Even if it's fake, I don't see how it could electrocute her to death. Maybe she could have touched the AC power outlet, but at it seems like this thing at worst (sending the AC through the wire) would short out instead of sending the current through the body.

----------



If you have enough current at only 1 volt going straight through someone's heart, yeah. Through skin on the hands, no. I would have been dead from a car battery.

The charger is plastic so how can some one get electrocuted? I find that strange .
 

bassfingers

macrumors 6502
Nov 15, 2010
410
0
Wait, isn't this where a bunch of people stand up to call this article racist?!

Where are you guys? Come on, you blew up the threads in the previous article on this issue
 

Darien Red Sox

macrumors regular
Dec 13, 2010
216
7
CT, USA
some reason why UK prongs are safer
Image
those outlets have doors that shuts when nothing is plugged.

while the rest of the world stubbornly stuck on the two pronged power plug, no wonder people died of electrocution.
These have been required in most of the US for a few years in many locations (I think starting with the 2008 NEC), they don't cost that much more so it is a good idea to use them even if your state dose not require them. It should also be noted that it is always better to go above and beyond what code requires to have a safe system. In the state of Ohio there have been several electrical fires in new houses which would not have happened in other states because Ohio was and is still using an older version of the electrical code.
 

Darien Red Sox

macrumors regular
Dec 13, 2010
216
7
CT, USA
When I was a teenager, I unplugged our freestanding kitchen stove from the 220V wall outlet (we were doing some remodeling). I had one hand on the plug, my feet on the wall for leverage (it had been plugged in for decades), and my other hand on the stove for balance.

As the plug came free, my finger slipped and came into contact with the metal part of the plug. I felt the current go up my arm, across my chest, and down my other arm to the stove. It was very painful, but I didn't die, or suffer any burns that I could see, or lasting damage that I'm aware of. I didn't go to the hospital. I think I was lucky.

Whenever I hear people complain about how kids today aren't allowed to do all the dangerous things we did when we were kinds (and survived), I remember events like this and wonder how we did survive. A few of my friends did not make it to adulthood.

This might have been just 120, in the US 220 is made by running between the two hots rather than a hot and grounded (neutral). Note that grounded is different that the ground. Inside the range the oven is mostly 220V and the burners are 120V. The oven the burner is directly connected to one of the hots, and the other hot goes through the oven switch. This is why is is impotent to kill the power before working or cleaning the oven by had. To be safe when working with 240 I always kill it at the breaker panel before removing the plug outlet.
 

dernhelm

macrumors 68000
May 20, 2002
1,649
137
middle earth
by definition, electrocution is always fatal...so he either wasn't electrocuted, or he is dead.

Not to be a word troll, but the oxford english dictionary seems to disagree with you...

http://oxforddictionaries.com/definition/english/electrocute

Both the American and World dictionaries have the same meaning; injure or kill. I read the original thread also, and couldn't understand why no one looked it up. The origin of the word does not limit its currently accepted meaning. I think people just liked typing portmanteau.
 

orthorim

Suspended
Feb 27, 2008
733
350
*throws away 6 generic chargers*

You should really only use Apple chargers.

A friend of mine destroyed 3 iPods with a cheap 3rd party car charger. All replaced under warranty by Apple before he realized that it was the charger that killed them.

Also I recently searched for a 3rd party iPad charger. Cheap no name chargers were marginally but not a whole lot cheaper than Apple original ones. Brand name and more solid looking ones were as expensive or more expensive than an Apple 12W iPad charger, so I went with the Apple in the end.

If you want to protect your device (and your life too, apparently), get an original charger.
 

celo48

macrumors 6502a
Apr 9, 2010
656
189
Totally idiotic on several grounds: 1. It doesn't cost 25 cents. 2. You can't sell stuff at the price it costs to build, or you go bankrupt. 3. It could be built for 25 cents if you didn't care about it being rubbish quality and a death trap waiting for its next victim.

----------



There are even stories of unscrupulous sellers who sell you a boxed iPhone, but first open the box, replace the original chargers, headphones etc. with cheap fake ones, seal the box again, and sell the original items for a good profit.

So even if she bought an original, brand new iPhone, and never bought another charger, you couldn't be 100% sure that the charger was an official Apple charger.


Who said they should sell at cost? How much does it cost to make it?
 

Makosuke

macrumors 604
Aug 15, 2001
6,662
1,242
The Cool Part of CA, USA
Actually most US houses have both, the higher voltage for the range/dryer and the lower voltage for other stuff.
Just wanted to note that I had intentionally left that out because it's limited to large appliances that people very rarely can even get to the plug on, let alone mess with, limiting the hazard of (my house has gas appliances, so doesn't even have a 240 circuit). Also, as Darien Red Sox noted, in the US household 240 is between the two hots, while either individual hot is only 120 to ground, which is somewhat safer since you're much more likely to accidentally create a path from a hot to ground through yourself (by touching a hot) than a hot to hot (you'd have to have a hand on something shorted to each of the hot wires).

For commercial and industrial installations there's also, of course, 208 and 240V 3-phase, as well as 220/240V two-wire and 480V systems, but those aren't something most people run into in everyday use (and the plugs are usually better--twist-lock, for example).

You want really scary, try a 300VDC open-circuit PV array, which most these days are. In addition to the very high voltage (and relatively high current), it's DC, so you might not even get the chance to let go when the muscle contraction released on the down swing, and the only way to turn it off is to wait for it to get dark. I was doing measurements on a 2KW array with a carbon-block resistor (with lineman's gloves and a sealed box, of course), but you could actually see the electricity crackling between the plates of the resistor.
 

Liquorpuki

macrumors 68020
Jun 18, 2009
2,286
8
City of Angels
You want really scary, try a 300VDC open-circuit PV array, which most these days are. In addition to the very high voltage (and relatively high current), it's DC, so you might not even get the chance to let go when the muscle contraction released on the down swing, and the only way to turn it off is to wait for it to get dark. I was doing measurements on a 2KW array with a carbon-block resistor (with lineman's gloves and a sealed box, of course), but you could actually see the electricity crackling between the plates of the resistor.

Doesn't AC cause muscle contraction too?

Also something cool - here in LA, our distribution lines are rated for 4800 VAC delta ungrounded. Linemen work on them hot. Those dudes are brave
 

Makosuke

macrumors 604
Aug 15, 2001
6,662
1,242
The Cool Part of CA, USA
Doesn't AC cause muscle contraction too?
Of course it does. The (minor) difference is that, since AC voltage is a sine wave going through zero (either 50 or 60Hz, depending on where you live), it is off or relatively low voltage some percentage of the time which, at least in theory, gives you the chance to let go. The frequency is high enough that that may not actually be true (your muscles might not relax quickly enough to voluntarily let go during the fractions of a second it's zero), but it improves your chances at least. With DC, the voltage is constant, so the muscles are guaranteed not to have a chance to un-contract.

Again, it's possible that the frequency is high enough that it doesn't matter in practice, but I've always been taught that DC is a bit more dangerous for this reason. Certainly, that effect changes how you mechanically break a circuit--with AC, because the voltage is often zero, you can just open a contact and the arc will generally break itself within 1/30th (or 1/25th) of a second. With high-voltage DC, it can "stretch out" a standing arc, so you need magnetic blow-outs or some other method of preventing arcing.

Also something cool - here in LA, our distribution lines are rated for 4800 VAC delta ungrounded. Linemen work on them hot. Those dudes are brave
Lineman have to be certifiably insane so far as I can tell. You can find videos of the guys who work on live 30,000V+ distribution lines--they wear big, conductive suits and basically hop onto the wires from helicopters. Not a job any sane human would want to do.
 

Liquorpuki

macrumors 68020
Jun 18, 2009
2,286
8
City of Angels
Of course it does. The (minor) difference is that, since AC voltage is a sine wave going through zero (either 50 or 60Hz, depending on where you live), it is off or relatively low voltage some percentage of the time which, at least in theory, gives you the chance to let go. The frequency is high enough that that may not actually be true (your muscles might not relax quickly enough to voluntarily let go during the fractions of a second it's zero), but it improves your chances at least. With DC, the voltage is constant, so the muscles are guaranteed not to have a chance to un-contract.

Again, it's possible that the frequency is high enough that it doesn't matter in practice, but I've always been taught that DC is a bit more dangerous for this reason. Certainly, that effect changes how you mechanically break a circuit--with AC, because the voltage is often zero, you can just open a contact and the arc will generally break itself within 1/30th (or 1/25th) of a second. With high-voltage DC, it can "stretch out" a standing arc, so you need magnetic blow-outs or some other method of preventing arcing.

From what I know, AC let go current at 60 Hz triggers at a smaller amperage than DC, making it more dangerous at the same voltage. The freq change in AC also induces cardiac arrest, where DC will just make your heart freeze until the circuit is broken. Though I guess if you're working with high voltages, it doesn't matter, they can both kill you in a myriad of ways

Lineman have to be certifiably insane so far as I can tell. You can find videos of the guys who work on live 30,000V+ distribution lines--they wear big, conductive suits and basically hop onto the wires from helicopters. Not a job any sane human would want to do.

Yeah I seen that video. :D They get paid bank though. One of the only jobs where you can get to six figures with only a high school diploma.
 

nec207

macrumors 6502
Mar 21, 2011
429
0
From what I know, AC let go current at 60 Hz triggers at a smaller amperage than DC, making it more dangerous at the same voltage. The freq change in AC also induces cardiac arrest, where DC will just make your heart freeze until the circuit is broken. Though I guess if you're working with high voltages, it doesn't matter, they can both kill you in a myriad of ways



Yeah I seen that video. :D They get paid bank though. One of the only jobs where you can get to six figures with only a high school diploma.

She may have touch outlet but no way you can get electrocuted from charger that is plastic .

I don't think AC or DC has any think to do with it .You can get electrocuted from both.
 

Makosuke

macrumors 604
Aug 15, 2001
6,662
1,242
The Cool Part of CA, USA
From what I know, AC let go current at 60 Hz triggers at a smaller amperage than DC, making it more dangerous at the same voltage.
Not quite sure what you mean by that, but I'm not a doctor, and it's quite possible that the AC, if you don't (or can't) let go actually ends up being more likely to stop your heart. In any case, like you said, either is quite capable of killing you.

She may have touch outlet but no way you can get electrocuted from charger that is plastic .

I don't think AC or DC has any think to do with it .You can get electrocuted from both.
You're correct that you can get electrocuted by AC or DC, but like many in this thread have said, there are a number of ways in which a faulty charger, possibly coupled with bad house wiring, could have fed 220V AC to the conductive outside case of the iPhone through the ground line of the charging cable. That the outside case of the charger is plastic is completely irrelevant--it has wires coming out of it going to the phone, which itself has a conductive outer case.

What you're saying is like saying you can't get electrocuted by your toaster because the power cord is coated in rubber.

.... and this. Apple will regret throwing suppliers under the bus
What on earth does Apple inspecting Foxconn factories for safe labor practices have with someone who bought a knockoff charger (no doubt not made by Foxconn) in China? (Probably bought from a fake Apple store selling counterfeit Apple accessories at a huge markup.)

It's utterly and completely irrelevant, unless you're implying that Foxconn--one of the largest manufacturing companies on earth--has a James Bond villain evil scheme to dump dangerous knockoff iPhone chargers on the Chinese market hoping that they will electrocute some people and give their largest customer a bad name. I mean, it's not like they might, you know, get CAUGHT when somebody investigated the deaths and figured out where the faulty chargers came from, which could result in their being punished by the Chinese government (which has been known to execute people for dangerous consumer practices), and would most certainly make Apple, their largest customer, really, really angry.
 

komodrone

macrumors 6502
Apr 26, 2011
499
0
You should really only use Apple chargers.

A friend of mine destroyed 3 iPods with a cheap 3rd party car charger. All replaced under warranty by Apple before he realized that it was the charger that killed them.

Also I recently searched for a 3rd party iPad charger. Cheap no name chargers were marginally but not a whole lot cheaper than Apple original ones. Brand name and more solid looking ones were as expensive or more expensive than an Apple 12W iPad charger, so I went with the Apple in the end.

If you want to protect your device (and your life too, apparently), get an original charger.

I personally don't care if my device goes bad, but I didn't know they can kill.
 

Matthew098

macrumors newbie
Jul 23, 2013
6
0
Cambridge,MA
Although using knockoff charger is the main reason of this tragedy, actually, we should learn that when your phone is charging, you cannot call or answer a call, even with the orginal charge, and no matter what brand the phone is. Because there is strong electricity and radiation when a phone is charging.
We should realize this and try to avoid such dangerous actions!
 
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