How do you safely discharge the power in a computer monitor?

Question

I want parts off of my old computer monitor but I don't know how to discharge the power from the CRT safely so as not to get shocked. Please help! I know other parts also hold power but I don't think they hold enough to actually hurt me. If there are other parts that can also hurt me please include those parts and other info in your answer.

Answer 1

To properly discharge the monitor, you need to make sure the power cord is unplugged from any power (as many have already stated), carefully remove the case to expose the main picture tube, then using a long metal screwdriver with a insulated plastic handle, carefully slide the tip under the large rubber, suction-cup looking attachment on the top or side of the tube with a single large wire attached, until it hits the middle of it and touch the metal shaft of the screwdriver to any metal chassis part of the monitor (some people will attach a heavy gauge wire with alligator clips to the screwdriver shaft & the chassis frame, which works well if a metal frame is not convenient for just the screwdriver). Use only one hand so that you don't accidentally complete a circuit with your other hand as you perform the procedure (you can wear gloves if you like so you don't accidentally touch metal while doing this, but they won't protect you from the discharge if your hand is too close). If there is a charge left in the tube you'll see & hear a spark jump as it discharges. Wiggle it around a little to make sure it's fully discharge & you should be good to go. If it's been off for several months or years, the charge may have already dissipated & any other capacitance charges would have been bled off too, but if it was on or plugged in recently, you may want to wait an hour or two to make sure any other capacitors have discharged fully too, but I've never had any problems with them when I used to work on them, the biggest concern was the picture tube itself that could hold anywhere from 20,000 to 50,000 volts of charge.



I couldn't find a decent video off-hand, though I'm sure there's probably one out there, but most I'd only rate as fair.

Answer 2

It never amazes me what stupid things people will tell you to do.



Never assume there's not enough juice left in those old capacitors to hurt you either. There's a good reason you don't go poking around hi-voltage circuits, even when they're off, until they're fully discharged.



The way we used to do it in the old days of CRT monitors so we didn't get zapped was this:



1. Turn off the display, and unplug it from the power source. Physically remove the plug from the monitor as well, so it doesn't accidentally get itself plugged back into the outlet by magic or stupidity from someone coming into your work area when you're not around.



2. Once it's unplugged, turn the monitor's power switch on to discharge any remaining juice left in the capacitors. Give it a good minute before you start poking around the circuits, as some larger capacitors take longer to discharge.



The flash you see on a CRT monitor when you turn it off indicates the high voltage circuits are working - that was one way we used to determine if they were working properly or not.



There's an old saying among us long time Electronic Techs - "There are Old Technicians, and there are Bold technicians, but there are no Old, Bold Technicians".



Keep a health respect for any electricity, be it AC or DC.

Answer 3

There is a big fat condenser on the power circuit board. This needs to be shorted out (connect + to -) There may not be much charge but advisable to wear safety goggles just in cas. Google 'discharge TV capacitor' There are videos and articles showing how to.

Answer 4

If the current is a constant thing as in it happens when the machine is plugged in it could be because of some wiring problem in your house which causes a reverse flow of current which will shock anything which is in contact with it and the floor or your monitor could be screwed up.

Answer 5

It's simple. turn off your computer by presing Start and Shutdown. then turn off the switch on located at the back of the computer. then unplug and there will be no power running through any of the computer parts.