Power Supplies and Monitors

[awwall]

Great advise Qball

[JC]

I took a AC/DC circuits electronics class at a community college. At the end of the class you would make a project kit. I chose to make a strobe light. I unplugged it and left it to have lunch. My friend touched it and got a big shock. It was not plugged in but it still had its charge. Hey, do you think that I could use that class to get a job at a pc store?
JC

[qball]

Not that I really care, but...

I've noticed quite a few posts regarding power supplies. I am amazed at how blase a few people are regarding safety issues concerning said power supplies. I haven't noticed much about monitors, but they can be dangerous also.

Anyway, basically one shouldn't mess with internals for a PC whilst it is plugged into an outlet, regardless of whether the PC is On or off. The reason being, on a lot of cases (ATX, most certainly), the power switch is a soft switch and even though the PC is not on, power is still running to the power supply, this can cause some bad things to happen. Iffin your gonna work in the box, unplug the power cord from the back.

Additionally, both the power supply and monitor contain quite a few capacitors. Capacitors, for the electrically challenged, store charge on conducting plates separated by insulating material. They store this energy until discharged, regardless of whether the circuit is live or not. One way to discharge a capacitor is to short circuit the leads. Another way is to contact the hot lead to ground. Both can be accomplished by touching the leads of a capacitor.

In conclusion, care should be given when working with and trying to fix PC parts. Not even going into the affect static can have on certian parts... Most don't have the technical knowledge to fix power supplies or monitors. When these parts fail, they should be handled very carefully.

I know my life is worth more than a $40 power supply, not really sure about the $400 monitor though...

End diatribe, thank you and have a pleasant afternoon.

[KillerBug]

Unplug and then try to turn it on, that will drain waht is left in it out. and DC powerr is all that comes out of an ATX power supply, they made it that way for a reason, it is all DC, and under 12v. And the only power running it from the 5v lead to the motherboard. No threat there. The only remote threat is in AT cases where 110 lines run to and from the switch, a screwdriver in the wrong place could be bad.