Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

ray648

macrumors regular
Original poster
Jan 10, 2008
118
0
Earlier today when i touched the aluminium part of the keyboard on my iMac, it felt tingly somehow, then a minute later when I touched the casing of the iMac itself I got one hell of an electric shock from it. Ive checked the cable and mains socket, and the earth connection is fine, so thats not the problem. Later on in the day I got another shock from the keyboard. I would normally blame things like this on a static build up in me, but I didn't get shocks off anything else, just the computer. Its switched off for now just in case. Its the 24" model, and I think its still the latest version, got it just after leopard was released. Any ideas?
 
I get shocked occasionally when I first touch the aluminum keyboard. I know in my case this is static discharge. My house humidifier isn't working, and this winter I get similar shocks touching any grounded thing in my house.

Given that this is the "shocking" time of year, and the aluminum body of the iMac and keyboard are surely grounded, I'm betting the shocks you are getting are static.

Can you get a shock touching the metal case when the imac is off?

Are you consciously or perhaps unconsciously creating more static as you sit there in front of the iMac? I've got a vinyl covered chair that will help me build up a considerable charge, especially when I'm wearing a sweater or such. It also adds to the problem if you are wearing relatively insulated shoes. When I feel it's a particularly shocking day I'll take my shoes off around the house. It lets me continually discharge through my socks into the carpet.

It's a little scary, I know. I've gotten in the habit of touching the metal leg of my computer desk before I touch my keyboard. Any shock I've built up will discharge into the leg, and my imac will treat me right. ;)
 
as above really,

It's most likely that your the one shocking your poor little iMac :(

If there was anything inside the iMac touching the case that could cause a shock it's fairly safe to say your iMac would be toast by now. I haven't stroked a alu iMac yet (I plan too...) but with a lot of metal cased small computers if you stroke the case while it's on AC power you can feel what i'd describe as ripples on the surface. While i'm a bit hazy on the subject, as far as i know it's due to a less than perfect ground within the computer somewhere allowing some 50hz hum to get to the case.


Now, the tingle is nothing to worry about, but the shocks are. If your charged up and stick your finger in a USB port bad things *could* happen, best bet is to ground yourself first on a radiator, metal desk leg, anything like that :)
 
I get the some times when I walk on on carpet then use my iMac, I stoped walking around in socks and it helped.
 
Starting about 3 days ago I started getting shocked from my aluminum keyboard. It just likes to move those electrons along.
 
It should be a feature

I think because :apple: has very sophisticated systems. I think the SMS is a similar feature at :apple: notebooks. It could have API as well. It's brilliant. I'm gonna check on the :apple: devcenter.
 
ow

I get some pretty nasty shocks from my iMac keyboard. It's not static though, it's definitely an electric current. You know how you'll feel tingling from an electric current? Yeah, that happens and it seems like it's beginning to get worse. I haven't gotten one directly from the iMac like you said, I think about poking the Mac itself after I get shocked but just can't. :(
 
If you believe it is current, not static, then test it with a voltmeter. one probe to ground and one to the surface of the device.
 
Make sure it has a good connection to ground (the third prong) and/or try another outlet. It could be leakage current (ground loop).
 
I eventually solved my problem. It turns out the earth was disconnected in one of the mains extensions I was using elsewhere in the room. Every time I played my bass guitar (amp was plugged into the extension with no earth), I would pick up charge, which then gave me a shock when I touched the keyboard.

If you are getting shocks then its probably some sort of earthing issue. My advice is to pick up an earth tester (looks like a plug with a light on the back to show if the earth works or not), and test all the sockets. You should be able to find a cheap one online somewhere easily enough.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.