Teen electrocuted while salvaging parts from a computer

Pushing the power button has absolutely no effect on the remaining charge in the capacitor. The boy opened up a tightly sealed box (the one that the power cord plugs into directly) ignoring the giant yellow 'WARNING' stickers that say not to do that.

One thing I do know is when my resolution was so high my screen was stuck black, unplugging my computer and holding in the power button fixed it. I would never advise a none pro to open a psu, but it sure seems like holding in the button uses the electricity, which for some reason beyond my meager understanding of computers was supposedly the cause of my video card resolution changing on its own correcting my problem, going back to default perhaps?

Meager in comparison to a lot of these techspot pros .

I think that will have discharged some capacitors, but not the capacitors (I.e. the big meaty ones in the PSU!)

@Per:

I read your post, and found a good schematic on the net that covers supplies with APFC. I tried to post it Friday, but for some unknown reason, I was unable to post it. http://resources.vr-zone.net/uploads/11366/ATX_power_supply_schematic_PFC.png

Because in that schematic the filter caps are approximately 2mF and at that value with even a 400V charge there would still be only about 80J in the capacitors, I am still having trouble with the reporting that states the kid had unplugged the supply. I highly doubt it was accurate.

Personally, I think it would be interesting if someone connected a modern, high-impedence volt meter across the filter caps in a supply that is powering a working computer, then either shut off the main switch or pulled the plug from the wall, and watched how rapidly the filter caps discharge. My bet is that they would discharge in a relatively short period of time which would be further evidence that the kid had not unplugged the supply.

There is a sure fire way you can prevent things like this happening ... when you open your psu ask your mate to touch all the components removing any risk to yourself . I have opened PSUs in the past normally to change fans or add some new cabling to power non pc items

May the best man live!!! This game would be energizing for both parties at the very least.

When I was doing my aircraft electrical degree the best fun was charging a large capacitor bending taggs close together and throwing them to unsuspecting airframe guys they got lots of buzzes outta that LOL

Did the Police check if the father recently did anything to upset the bankster cartel, like that guy who reported on the 43 Trillion dollar lawsuit against them and had his kids killed the next day as a warning to other Journalists?

Cause the capacitors don't keep power long enough to give you time to unscrew the four screws it takes to actually open it up and get your hands inside...

I've worked on enough of them to know...

I read recently that the average human heart is pulsed electrically within the body and it is extra susceptible to being stimulated into fibrillation during about 1/7th of the cycle of each heartbeat. This is from the book "Overcurrents and Undercurrents" by Earl W. Roberts. When this happens a defibrillator is required to stop the heart and initiate the correct beat.

Most of these comments are about as full of stuff as the original story. Someone posted about the human heart beating at 60 Hz? Really? Are you the FLASH?

If I were the police there, I'd be checking the father's story. I suspect someone plugged the supply back in. Intentionally or accidentally is the question.

I own an Electronic Waste Recycling company. This is a very real unspoken danger I see a few times a year, normal just a tiny zap. But in larger commercial equipment, they have much larger batteries than the quarter battery on a mainboard...can get scary- MONTHS after it's been unplugged..

I'll reply since this has been bumped to the top of the stack. What you're saying is only partially true. In most circuits, the + terminal of the capacitor is connected to the load. If that is not the case the cap just charges to full and stays that way. They can hold charge for quite a while, and it doesn't matter if you pull the plug, or shut off the switch, they'll nail you big time, if you're anyhow grounded when you touch the positive lead.

The lethality of any given electrical charge is determined by the amount of charge delivered. On dry skin with a poor ground it takes quite a charge to kill a person. delivered close to the heart and subcutaneously, it becomes a matter of microamps.

Capacitors don't sustain the delivery of the charge. However, when a human touches a live wire with continuously flowing current, there exists a "no let go" threshold, when the current causes the muscles themselves to contract involuntarily, and out of the their owner's control. These are the most often causes of electrocution, a sustained contact with continuously flowing electricity. Although, lightning kills quite a few people a year. It's a short term event, but with millions of watts seconds of charge, it's fast acting! (Citation required).

It's also the operational principle behind the defibrillator, which clamps the heart muscle solid, and hopes that the heart itself will resume normal sinus rhythm, after that event. Keep in mind, to deliver that charge, a conductive paste is applied to the chest, and the charge delivered to the chest can be as high as 360 watt seconds. That's why they yell "clear". Cause if you're touching the body, you're going down.

And that boys and girls, concludes our feel good, necro-bump, bedtime story for tonight Nighty, night.

Total energy doesn't really mean anything... you could sit there for years with a trickle current running through you and it won't kill you.

Or, for cheap thrills, you can stick a 9 volt battery on the end of your tongue.....

Is it strange for a person's heart to beat at a very healthy 60BPM?

You do realize 60Hz would be 60 beats per second.

See, this is what happens when you abandon the old nomenclature. When you meant " 60 CPS", you said, "
60 cycles per second". There was none of this "60 Hertz" bull s***!

And kilocycles meant CPS counted by thousands. Same deal with megacycles.

captaincranky, I'm not following. What is it I am abandoning? Hertz was already mentioned, the comparison did not originate from my comment.

The hertz is equivalent to cycles per second. The heart beat represents a complete cycle, though I'm not sure if it actually has to beat twice to complete a cycle.