Computer Power Supply?

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Killjoy
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Sun Jan 06, 2008 1:28 am

I think it's 15 milliamps
I thought they said 6 milliamps, but I've also heard that its 100 milliamps will stop you heart... I'm not sure though.

Human skin has a relatively high resistance, so my understanding is that 12v is not high enough to allow a full flow of current and therefore is relatively harmless.
Now if your skin is wet or you pierce your skin as this guy did
http://www.darwinawards.com/darwin/darwin1999-50.html, then the resistance would be extremely low and allow a lot of current to flow.
(not sure if that made since).

I'm sure Jimmy could answer correctly

Edit: damn it singularity beat me, but what he said is right.
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VH_man
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Sun Jan 06, 2008 8:38 am

thank you guys, ill use this to "wage my war". lol.

i dont want to spend 500 bucks on a power supply when i can get one of theese for free.........
TurboSuper
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Sun Jan 06, 2008 9:17 am

You won't hurt yourself with a computer power supply. Like singularity pointed out, ohms law dictates that you won't get enough current through you to stop your heart with only 12V.

Ask your dad if he could kill himself with a car battery, same idea.

That being said, make sure you're not wet while touching it.

Oh, and as for the little dilemma about lethal currents, once again, wikipedia solves everything :D :

http://en.wikipedia.org/wiki/Electric_shock
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ralphd
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Sun Jan 06, 2008 9:57 am

it's 7 miliamps that kills......as for a good sources of knowledge try

engineeringtoolbox.com
extremetech.com
discovercircuits.com
howstuffworks.com
ttr.com
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DYI
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Sun Jan 06, 2008 10:07 am

7 milliamps across the heart can kill. Your body's resistance will cause the current to decrease the farther it has to travel through your body, and when travelling through anything, high amperage low voltage dissipates more rapidly than high voltage low amperage. Thus the reason that while a car battery can cause severe burns and damage to limbs, it is very unlikely to kill in most circumstances*

*sticking the electrodes into your blood vessels and then attaching them to the electrodes of the battery does not count as "most circumstances".
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benstern
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Sun Jan 06, 2008 3:12 pm

Stop comparing to a car battery same voltage yes. But a psu amperage is much lower.
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Fnord
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Sun Jan 06, 2008 3:15 pm

Be aware that some older power supplies have a live 120 line running from them which is used for the switch. I found out this the hard way when I was trying to start an old psu manually* to run some small electronics.

With newer PSU's, you are completely safe as long as you don't try to take a bath with it or run it without the case on.

*Involves jamming a paperclip into the leads to find the power-on circuit. I wasn't grounded, so I didn't get shocked, but I did get some nice sparks and that evil "burning electronics" smell
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psycix
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Sun Jan 06, 2008 5:47 pm

I use a PC-PSU for hobby electronics for some time now.
I dont have it fit into a pc but I run it on its own.

To run one on its own just connect the green wire in the 20-pole-plug to a black one and it will turn on. Thats the power-on circuit.
Check the internet for more details.
I soldered a switch between them. ;)


And I even soldered metal clamps on 12, 5 and GND wires so I can clamp on anything I want.

When I short-circuit it just shuts off and can be turned on again without problems.
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benstern
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Sun Jan 06, 2008 6:22 pm

http://www.helpwithpcs.com/courses/powe ... inouts.htm

Thats a great resource for determining the pinouts.
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