[sd_smoker]

Lately when I touch the back of my computer I can feel a tingling sensation. It doesn't shock me like a static discharge would, but it's just a steady tingle. I just replaced a bad motherboard, that I suspect may have been damaged by this. Yesterday my computer locked up and when I felt the back, the current felt stronger than normal. I unplugged the power supply and it was reduced, but I could still feel it. I unplugged the monitor and it was reduced some more (but I could also feel electricity if I touched the unplugged monitor cable which was not connected to the computer). I unplugged the printer cable and it finally went away. Could the problem be in the power strip/surge protector? Somehow that doesn't seem right...


I thought it was a bad power supply (the unit in the computer), but then how come I could feel it in the monitor cable? I thought maybe we had too much voltage coming into the house (we've been losing lightbulbs fairly often), but there is another computer plugged into the same extension cord as the computer with the problem and it is fine so far. It is using a different power strip though. I'm at a total loss and I'm afraid to try and start it back up for fear of losing a brand new motherboard that I can't afford to replace again. Anyone have any ideas? TIA!

 

[Al Sherwood]

Definitely sound like you have a problem with an ungrounded circuit. The tingling sensation you speak of is the electrical current finding it's way to ground through you! Unless you like this feeling, I would recommend that you stop this practice and find the problem


You are correct, you have to eliminate each piece of AC connected equipment. Your statements are hard to follow, for example: (but I could also feel electricity if I touched the unplugged monitor cable which was not connected to the computer). The power cord or the video cable?


The most interesting statement is about the printer:"I unplugged the printer cable and it finally went away" Plug everything back in except the printer (use the same power bar) carefully touch the back of the computer, if there is no tingling sensation, the printer's is at fault. If there is then start here.


Try the computer and monitor only plugged into the powerbar, tingling? if so eliminate the powerbar, tingling, fault is with the monitor or computer, no tingling then the power bar is at fault.


Let me know the results and I'll suggest a further course of action. Remember this though, each electrical connection the you have is a source of ground problems, as are cable and phone connections, all of these must be checked until you find the culprit.


But be CAREFUL, electricity can BYTE!

 

[sd_smoker]

I apologize for the incoherence of my original post. Let me clarify. If I leave the monitor plugged into the power strip, but disconnect it from the computer, I could feel a slight tingle in the unplugged end of the monitor's video cable. Does that make sense?


I'm beginning to think that the problem is not the computers power supply, or at least not the power supply alone. It just wouldn't make sense since the monitor appeared to have the same problem when not connected to the computer. Besides, the fact that each time I unplugged something from the computer it got a little better would seem to indicate the power supply.


I'll check when I get home from work and let you know what happens. If you don't hear from me, send an ambulance...

 

[dandrewk]

First thing to do: Turn everything OFF.


If you or somebody should touch that computer with, say, wet or damp hands, it could be "lights out". Literally.


Unplug everything and put that box on a bench where you can test it. With rubber gloves, if necessary.


And please don't think a circuit breaker will protect you. The best thing would be to hook it up to a GFI circuit when working on it.

 

[Lee L]

If that thing is leaking current the GFCI will trip out right away so that might be a good test in and of itself.


Buy one of the little outlet testers you plug in and the three lights tell you what is up with that receptacle's wiring. For 8 bucks, that is a good thing for anyone to have. If that doesn't tell you right away you have a problem with the outlet or the powerstrip go and buy a meter from Rat Shack or your fovorite home improvement store. Use that to test for current leakage and voltage from the cases of your equipment to ground.

 

[sd_smoker]

Alright, get this. The knucklehead that wired the garage (now the office/cigar room) reversed the hot and neutral on this outlet AND he never connected the ground wire to the garage!! And it only cost me a new motherboard/cpu to figure out there was a problem.


Luckily my brother-in-law is an apprentice electrician and was able to figure this out. He rewired the outlet and connected the ground wire (it was already there, it was just disconnected ). Everything works perfectly now!

 

[boykster]

yikes, nice catch....that have caused some major damage (motherboard aside).


Rich

 

[Al Sherwood]

Good to hear the problem is solved, I guess that the knucklehead thought that a ground wire was just an extra!


I bet he said "Hey, it's only a bunch of wires, how hard can it be?"