Perspiring man electrocuted by his PC

A 20-year old student in Shanghai's Yangpu District perished after being "electrocuted by his computer." Reportedly, the man removed the external case from his desktop to prevent it from overheating in the non-air conditioned room, and when his legs came into contact with the innards, the resulting shock left him deceased. Initial investigations by local police confirmed that he was indeed electrocuted, yet there was no reason given as to why the individual refused to switch on the cooling system.

[Via The Raw Feed]

[Blake @ Jul 31st 2007 11:46PM]

Pwnt.

[paul34 @ Jul 31st 2007 11:47PM]

Maybe you didn't notice, but this guy is dead...

[Blake @ Jul 31st 2007 11:54PM]

I noticed, hence the "Pwnt."

[fischju @ Aug 1st 2007 1:14AM]

Honestly.....survival of the fittest

[nih @ Aug 1st 2007 1:42AM]

He told you he was hardcore.

[Dustin @ Aug 1st 2007 2:10AM]

Darwin award....check

[RedBull Runner @ Aug 1st 2007 10:51AM]

Look, this is hilarious, and it was stupid of him to go against the warnings on the stickers ALL OVER THE BOX. If something says DANGER! HIGH VOLTAGE! all over it, and you still open it while its running, then you deserve to die.

[paul34 @ Jul 31st 2007 11:49PM]

>> individual refused to switch on the cooling system.

May I ask what you mean by this comment? Did you mean in his PC? What cooling system? Everything was already running. I'm quite confused.

[Dan @ Aug 1st 2007 12:29AM]

I think they mean his air-conditioning, but it says he didn't have one.

[Captain O @ Aug 1st 2007 12:40AM]

the air conditioning, in the room. it seems pretty obvious from the post.

[paul34 @ Aug 1st 2007 12:35PM]

Well, the article already said there was no AC in the room... thus my question.

[DJBro @ Aug 2nd 2007 2:05PM]

the room had air conditioning, but it wasnt on. it was therefore non-air conditioned at the time he was electrocuted. the police told reporters that he was indeed electrocuted, and im sure one of the reporters asked why he didnt just turn the AC on, to which the cops replied, we dont know.

[greymullet @ Aug 6th 2007 9:24AM]

I just figured that, being an American site, Engadget assumed that everyone has AC. That might be hideously unfair of me.

[divakchopra @ Jul 31st 2007 11:54PM]

That computer looks deadly alright!

[Thief @ Jul 31st 2007 11:54PM]

That's really sad ;(
I've gotten a shock from powersupply before, but I wonder what gave him enough jolt to kill him...

[Alex @ Jul 31st 2007 11:58PM]

How could he be exposed to voltage over 12 volts inside a normal computer? The power supply takes care of the 110/220 volts unless its an old emac type computer with a crt in it.

[Thomas Bags @ Aug 1st 2007 12:02AM]

Thats what I thought too

[Pie Pants @ Aug 1st 2007 12:28AM]

Just because it's low voltage, doesn't mean it can't kill you. If he was indeed "perspiring" as the title suggests, then that could lower his skin's resistance enough for the few amps the power supply puts out to be fatal.

[dan @ Aug 1st 2007 12:34AM]

Volts don't kill you, current does. gb2 basic electronics

[Ratchet the Lombax @ Aug 1st 2007 12:37AM]

It's not the voltage that can kill you it's the amps. For instance a stun gun can have 50,000 volts but very low amps therefor it won't kill you. All you need is 6 milliamps across the heart to cause cardiac arrest and I'm pretty sure a computer has at least that or more. Also moisture and the salts in the sweat could have amplified and also given a more direct path to the heart. Plus 110 volts can be more dangerous than 220 or 440 as it "holds" you to the source as opposed to throwing you back like the others so you get a longer charge from it.

[NovaLand @ Aug 1st 2007 1:21AM]

The original article mentions 380V, which is two or/and three-phase powersupply, which isn't your regular household computer. So if it is a mainframe computer, that would partly explain why the individual would refuse to turn on the air condition, due to that the sum of both running a mainframe and using an AC in an enviroment that wont let you use that much power at the same time.

It does not however explain why live parts were exposed in such way the individual would come in contact with them. He might have removed any cover for the PSU because that might have been one of the parts that were overheated and not the CPU or GPU as in a regular standard computer.

[David @ Aug 1st 2007 1:27AM]

Chinese power supply is 220V. That is enough to suck you in and electrocute you pretty fast. I remember when my mother told me back in China not to play around the huge transistor because of this very reason.

[NovaLand @ Aug 1st 2007 1:30AM]

@Ratchet the Lombax: True that it's the amp, but i am quite certain the bodys internal resistance makes sure the ampere will be kept kinda low at low voltages unless you somehow short-circuit you heart directly which in this case did not happened. It was his leg that came in contact with the live parts. And about the stun gun issue, deaths have occurred, but usually on individuals that are sick/old or have other issues. There's a difference between the small ammount of power needed to prevent your heart from controlling itself and the chock you get from a stun gun. Both can be lethal.

[Michael Geary @ Aug 1st 2007 1:41AM]

You guys have the current issue all mixed up. Sure, if you get enough current through your heart it will kill you, regardless of the voltage. But there's no circumstance where 12 volts through your body will produce enough current to harm you. Your body's internal resistance is much too high.

Suppose you get your hands wet, salty, and as conductive as you can make them. Now you grab the two sides of a 12 VDC power supply, positive in one hand and negative in the other.

It's very unlikely that you will even feel any current. You certainly won't be hurt. Heck, you could attach needles to each terminal and poke them in your fingers, bypassing your skin resistance completely. You won't be electrocuted. Your worst injury will be from the pinpricks.

Take a couple of 9 volt batteries and snap the + of one and the - of the other together, so now you have 18 volts across the two exposed terminals. Get your hands conductive again and press a finger of each hand against those terminals. Still not enough to hurt you.

Stick one of the contacts against your *tongue* and grab the other with a wet, salty hand. Still nothing. You might get a bit of a tingle on your tongue, but nothing like the tingle you get when you touch your tongue across the contacts of a single 9V cell. (You've done that, haven't you?)

And it's not because a 9V battery has limited current capacity compared to a 12V power supply. It's all about your body's internal resistance. Low voltage across high resistance equals low current. It has nothing to do with how much current the power supply *could* deliver. With that high resistance, it just won't deliver much.

What could have killed the guy, then? A ground fault is a very likely possibility, as Hemat suggested. Or some other kind of electrical fault. Not 12 volts.

[Dennis @ Aug 1st 2007 7:34AM]

@ Ratchet:
1mA across the heart is enough to kill (depending on the individual).
3mA across the heart causes ventricular fibrillation which can cause death.
6mA across the heart almost guarantees death.
Also 110V is not more likely to hold you than a 220V supply. It again depends on the current flowing through the muscles. 1-2mA causes sustained muscular contraction.

@ Michael Geary:
The human body doesn't actually have that high an internal resistance. Blood is a great contuctor. Its only the skin which provides a high resistance - dry skin has a resistance of about 10kOhm, and damp skin about 1kOhm.
Doing the maths: V = I x R
1mA through a 1kOhm resistance, needs 1V across the skin.
Even if he had dry skin:
1mA through a 10kOhm resistance needs 10V across the skin.
So in fact 12V from a computer power supply is sufficient to cause at least some damage.

[DakStaka @ Aug 1st 2007 8:14AM]

@Denise

Show me your reference for those resistance figures. 12v isn't going to kill you.

Michael Geary has it right... and most likely a ground fault and the fuse at the switch is either hard wired or there is not a fuse at all!

[Josh S. @ Aug 1st 2007 12:01AM]

I totally don't understand this - what computer has enough voltage running through it to kill someone? I think there are some missing details .

Unless I have no idea what I am talking about, which is quite possible. Feel free to correct. A sad story either way.

[Josh Brunelle @ Aug 1st 2007 12:13AM]

Doesn't matter how much voltage hits you, it's the current. Considering the current carried in a typical psu, it could easily kill you.

[Chuckles McGee @ Aug 1st 2007 12:04AM]

I guess the advice "Don't sweat it!" really could be a lifesaver. Shocking how that stuff helps.

[Trace The Hedgehog @ Aug 1st 2007 12:08AM]

in before the "should have gotten a mac" comment from some iboy.

[Zach @ Aug 1st 2007 4:12PM]

im not going to thread jack, but i'd like to point out:

my mac has never shocked me once. the kid should have gotten a mac, bill gates is obviously trying to kill ou

[DaCheetah @ Aug 2nd 2007 2:32AM]

Bill Gates doesn't make computers, he runs a software company that also makes a few peripherals. And my PCs never shocked me, and I swap parts out while it's running, something that could easily be fatal in an old CRT using iMac.

[Jenny @ Aug 1st 2007 12:08AM]

This sounds like an urban legend. Where did it happen?

[Jenny @ Aug 1st 2007 12:08AM]

Nevermind, I see the where. Still sounds like an urban legend.

[JC @ Aug 1st 2007 9:08AM]

Your mamma's an urban legend.

[Mark @ Aug 1st 2007 12:08AM]

The only thing in a computer that could come close to killing someone would be the capacitors in the power supply, those things are heavy duty but still you'd have to really try to get at the contacts on those. Something seems fishy about this.

[Keaton @ Aug 1st 2007 12:19AM]

I seriously couldn't see how this could happen.... Did he have the PSU cracked open? Jeez if so thats idiotic.

[Alex @ Aug 1st 2007 12:37AM]

if he had the psu opened then i think it would be Darwin's law in effect

[Terc @ Aug 1st 2007 12:36AM]

"The young man, who was identified as Wu, reportedly opened the external casing of the computer's **CPU** to prevent it from overheating"

Erm... CPU... that's got a whopping 1.37volts passing though it, maybe up to 3 on very old computers. It's also a part inside a computer, and I'm not sure you can take the casing off. I guess the journalists over a shanghidaily.com don't undestand the difference between a computer case and a processor.

The world may never know if there's any validity to this story at all.

The only possibility I can come up with is that this guy actually took the casing off of the PSU (Power Supply Unit) and managed to get his leg on a capacitor, or worse, just made contact with cords running to the wall. If this is the case, I'm officially nominating this guy for the Darwin award.

[kyle allen @ Aug 1st 2007 12:43AM]

the tower is often referred to as the cpu. im sure thats what they meant.

[Juaquin @ Aug 1st 2007 4:31AM]

@Terc

Today my mother referred to my tower as a "hard drive". I kid you not.

[lao soup @ Aug 1st 2007 12:20AM]

CHINA? CCTV anyone?? They must've caught him spreading news to his fellow citizens so they came to his house and tasered him to death while calling it a computer "accident".

Its another step from the communist government to set an example!

[Bobo @ Aug 1st 2007 12:22AM]

Machine: 1
Human: 0

[kyle allen @ Aug 1st 2007 12:46AM]

ive killed my fair share of machines thank you verry mutch!

[halfeatenfish @ Aug 1st 2007 12:21AM]

You guys are assuming a normally working computer. It's not implausible that some sort of short was causing the case (or whatever metal in it he touched) to be energized?

[ashmist @ Aug 1st 2007 12:35AM]

I remember back in the day when I was obsessed with totally silent pc's, I took the PSU out of my old PIII and removed the outer casing so I could remove the last fan from the system. I just had the guts sitting on top of the CPU case under my desk. Ahh to be young and reckless again.....

[johnny hates waiting @ Aug 1st 2007 12:39AM]

Yea I believe this one. Let me explain. I lived in china before and we had built our own computer (not the best grounding in the chinese home grown power supplies). We had ac but our power was on a pay meter device just outside the door. So you had to get these cards to keep it full (kind of linke feeding a parking meter). So AC runs your credits down real quick. This guy probably had the choice between the computer or the AC. Second power is really bad in China. We had a voltage regulator and surge suppressor hooked up to ours. The power spiked really high (over 480v) and caught the computer on fire. If we had had the cover off, like we often did, i'm sure something like this could have happened.

[zz @ Aug 1st 2007 1:19AM]

yours is the only sensible comment here. thank you. i think it's hard for most of these geeks to remember that the rest of the world isn't like livermore or orange county. you guys really should get out more...

[Hemant Srivastava @ Aug 1st 2007 12:45AM]

In my experience, if you don't ground your box, there would likely be a float voltage across the transformer-less SMPS, which may spread to various parts of the box and any other device wired to it.

Then, if you are sweating or wet, and come in contact with a grounded object and the float voltage at the same time, enough current may pass through your body to, well, kill you.

When I said 'in my experience' above, I meant only the first part. I know you people realized that.

[Benno @ Aug 1st 2007 2:18AM]

Well, it's pretty unlikely that the PSU is transformerless. After the primary side rectifier and the primary FET there's usually a high frequency transformer in order to lower the switched voltage before recifying it again to +12V. Perhaps a forward or flyback topology type (or any of the other common ones). Theoretically you could get rid of the transformer but that would make the duty cycle so low that it would be difficult to regulate the output voltage. Another reason (or more of a bonus) for using a transformer in the PSU is to electrically isolate the input from the output.