And please do not forget, all you handy-men out there, that high voltage capacitors exist in many household appliances: TV's, Microwave ovens, Refrigerators, Receivers, etc. And some of these carry a much bigger wallop that a power supply. Be cautious around any electrical appliance!
When I was a kid, I learned the "fun'' way (getting knocked on my ample asset) that the picture tube of a TV acts like a high voltage capacitor. Before retiring, I worked in warehousing for an electric utility company and, every once in a while, some moron would drop off a capacitor bank (those things were huge) that didn't have the terminals shunted. We would call in a lineman or electricians to shunt it; you wouldn't believe the size of the spark they would draw off it while installing the shunts.
I always hold down the power button on my pc with the power supply switched on for around 5 to 10 seconds to drain power from the power supply and motherboard when I work on pcs. I notice that on my desktips, they power on for about a half a second and you can hear the fans start to spin up because that's how much energy those capacitors in the power supplies store. Always, ALWAYS drain the pwoer from a pc before working on it. You won't regret it in the long run.
When working on electrical devices, use the "Right Hand Rule".
If you only use your right hand, any current is less likely to pass through your heart.
Make sure you aren't creating a potential current path with your left hand too.
His death is tragic, yes, but he was not a geek. A real geek would have known better. A real geek would know how to discharge all remaining power before working on a PSU. Just like people who clean windows on skyscrapers know they should be wearing a safety harness at all times.
Apparently in the tech field, too often you see people who think they know it all, and sadly this is one of the more extreme results.
Truly tragic, a young life ended. Does not matter what label you pin upon the young man concerned: Geek or not, he leaves behind a grieving family.
I learned to respect electricity some 60 years ago, in the home of my parents. That was a National Coal Board estate house, as my dad was a miner. There was no "Health & Safety" at that time and the power sockets were placed wherever you wanted them. They were the UK "3 Pin" sockets and plugs, but at that date the pins were round and slotted, not rectangular and solid, as now.
One socket was fitted in the RH side of a window which was above the kitchen sink (yes really!) and there was a net curtain in the window, held up by a spring wire, all steel. The plug was often left dangling in the window, and on this day mother decided to take down the curtain. She dropped one end of the wire, which flicked across to the socket, and also caught the live pin of the plug. The socket switch was on. Circuit between mum, socket and plug being completed, she was thrown across the room and landed unconscious on the floor.
Imagine the effect upon a 7 year old boy. (me!) Mother fortunately recovered, although within a couple of years she began to suffer Angina pains. It was a lesson I never forgot and I have always respected electricity.
This is sad and really shouldn't have happened. The voltages on the output of a PSU are not lethal and perfectly safe to work with. There is the possibility of a burn in the case of a short but electrocution is virtually impossible. All of the potentially lethal voltages are isolated from the consumer by the PSUs metal cover. There really is no reason for the average "geek" to ever open the PSU since there aren't any "user serviceable" parts inside.
I learned to respect high voltage devices by working on high powered transmitters and power supplies capable of 500KW output (that's 500V with 1,000A). I once got shocked by 400V thru my arm from my little finger to my elbow. It hurt like he77 but there were no after effects. If that shock would have been from hand to hand the current would have passed thru my chest and I probably wouldn't be here today.
All it takes is 28Vdc and 50milliamps to stop your heart. Be careful people.
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