Can Feel Current Through Apple USB Keyboard?

Tucom

macrumors 65816
Original poster
Jul 29, 2006
1,177
248
Hey all, I'm using this Apple USB Aluminum keyboard that works and functions perfectly except for one bothersome thing -



I can feel current through the keyboard if I touch almost any corner of the metal of the keyboard.


It's plugged into an aluminum 20" Apple Cinema Display, and here's the interesting part; if I touch the display while touching one of the problematic corners of the keyboard, I can't feel the current anymore.


I had an issue like this a long time ago except I could feel the current on the back of my eMachines chassis (and this was when eMachines made AWESOME machines, especially for the price), and that was because the new room I was in wasn't grounded properly, and the wiring was such that if we left it any longer it would have been a serious accident waiting to happen.

However, I don't believe the place I'm living in now has any issues like that. If I touch the Cinema Display or Mac Pro itself I can't feel any current at all.

The ONLY thing I can think of is that before using this keyboard I wiped it down and cleaned it with one of those Clorox wipes or whatever, and I think some of the liquid from the wipe got into the keyboard itself beneath the keys, but how would THAT cause current to be transmitted to the top right of the keyboard, when the keyboard's at an incline?


Any and ALL info would be very much appreciated.
 
Last edited:

thedeske

macrumors 6502a
Feb 17, 2013
963
58
Try to recreate the grounding problem in another room (i.e. different circuit) by way of a long extension cable or just moving the stuff.
Had the same issue with Apple's current (no pun intended) wired keyboard.

Another test is use a different keyboard.
100mA is enough to tingle most of us ;()
 

m4v3r1ck

macrumors 68020
Nov 2, 2011
2,341
347
The Netherlands
When walking on shoes with lether on my carpet (synthetic) I sometime create such a huge static charge I could use it to fill my carr battery ;-(

Lessons learnt; so I know grab a hold onto the heatingblock (best grounded item here I think) in my office before touching any apples on my desktop! ;-)

SHOCKING ELECTRICA!!!
 

SMDBill

macrumors 6502
Apr 12, 2013
255
1
Plug the keyboard into some other device's USB port and see if you get the same result. Even a power charger/adapter. If you do, the keyboard is faulty. If you don't get the same result when doing that, you have an electrical issue in the circuit of the home the computer is plugged into (neutral or ground issue) or the computer.

Example: we had an AC unit repaired in a small building I worked in. It was raining outside and a technician grabbed the metal door handle (attached to a metal door) and jumped back, shaking his hand from the jolt. I was inside the building and dry, grabbed the same door handle and felt nothing. Because I was dry and had rubber soled boots on I was insulated from ground so I felt nothing, but he was in contact with the source of energy (door handle) and ground (being wet standing on pavement) so he was the conductive path. We found out the AC fan was removed and when they reconnected the wiring they crossed wires either phase to phase or something else, can't recall.

If you can't duplicate the problem anywhere but on that machine, either the outlet providing power or the internals of the computer itself are faulty in some way by energizing an electrical path that is probably supposed to be carrying ground, not power.