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Kirkman
Sep 7, 2006, 10:25 AM
Hey all... Recently moved into a house and hooked up my PowerMac G4 MDD.

Problem is that the metal surfaces on the computer give somewhat of an electric shock. I don't have a voltmeter, so I can't measure how much it is, but this definitely didn't happen before. Also, when my iPod is connected to the G4 through the dock, I also get a shock touching the metal surface of the iPod.

Anyone know what might be going on?

--Josh



TBi
Sep 7, 2006, 10:29 AM
i had this problem too but it was because the ground terminal in my socket wasn't actually ground. It was tied to neutral, which can be above or below actual ground. Thus when I touched the computer i was getting a shock from the difference between neutral and local ground.

disconap
Sep 7, 2006, 09:41 PM
Yeah, that makes sense. Check your outlets, and maybe try plugging it in through a surge protected power strip or something...

Makosuke
Sep 7, 2006, 10:01 PM
You almost certainly have a bad ground in the house--it's either bonded to neutral and floating awfully high, or there's something shorted to it.

Regardless, it's a safety hazzard for a number of reasons, and a surge protector won't make any difference (though some better ones WILL tell you when your building is mis-wired). I'd get an electrician to look at the place and see what's wrong--better now than after something starts a fire or fries expensive equipment.

disconap
Sep 7, 2006, 10:58 PM
On the safety end, I agree. But the surge protector will likely solve the shock on the comp (at least, it did with an old amp I had where I was experiencing grounding issues). It's not safe by any means, as it's still not grounded, but the surge protector took on the inequity, at least in my case.

law guy
Sep 9, 2006, 09:12 PM
Yes - you've got an outlet (or circuit) that doesn't have a ground (well, you ground it when you touch it, but that's not a good thing). A surge protector isn't going to help you - it trips in response to too much energy. What you're experiencing is not a case of too much energy it's that you are creating a path for a small amount energy when you touch metal parts - it's not a full blown shock. The only way to fix this is to get the ground fixed. You should do this anyway as 1) your outlet is not safe as is, and 2) you may have ground issues on the circuit or on your whole system and you don't want a family member to be electrocuted in the kitchen or bathroom (places where water is present and you're more likely to create the circumstances needed for a short that will deliver the full blown shock). The best thing to do is called a licensed electrician to check everything out.

disconap
Sep 9, 2006, 11:44 PM
Agreed. But one other thought--the outlets may not be grounded outlets, and someone may have installed a three prong plug, thinking it would make it grounded. If it is only this outlet (try a couple others in your house), either run a very high grade (outdoor designed is best) extension cord from another outlet, or try picking up a 2prong->3prong converter from Radio Shack. It's likely a larger problem, but there is the slightest chance that the ability to ground is there; those converters screw into the center screw on your outlet, which can (in some, SOME note) provide the necessary ground.

Of course, I still completely agree that you should get a licensed electrician to check out your system.