Electric shocks from computer case
 

I've started getting electric shocks from the computer case.

I've tried two different power supplies - I get shocks with both.

They are too strong to be static electricity IMO.

I put a voltmeter between the case and a rad pipe. I can't measure any
voltage on AC or DC, I've tried all the voltmeter settings up to 500V.

I've tested the voltmeter on a mains wire - it reads 230-240V
reliably.

Interestingly, if I use the circuit tester function, there is a
circuit present between the rad pipe I was using as ground and the
case. Could they both be at the same potential maybe?

Nick

Electric shocks from computer case
 

Interestingly, if I use the circuit tester function, there is a
circuit present between the rad pipe I was using as ground and the
case. Could they both be at the same potential maybe?


They could both be at earth potential. E.g. your radiator is bonded to
earth, your computer case is connected via the earth from the PSU.
Maybe it's *you* who isn't at earth potential. Could you be touching
anything else when you get the shocks? E.g. your table lamp is live. You are
leaning against it, but are well insulated so no current flows. You touch
your (earthed) computer case.... you fly across the room. I'm assuming that
this isn't what is actually happening, since you don't mention flying across
the room, but I think the concept has potential (sorry)

Electric shocks from computer case
 

NickW wrote:
I've started getting electric shocks from the computer case.

I've tried two different power supplies - I get shocks with both.

They are too strong to be static electricity IMO.

I put a voltmeter between the case and a rad pipe. I can't measure any
voltage on AC or DC, I've tried all the voltmeter settings up to 500V.

I've tested the voltmeter on a mains wire - it reads 230-240V
reliably.

Interestingly, if I use the circuit tester function, there is a
circuit present between the rad pipe I was using as ground and the
case. Could they both be at the same potential maybe?

Nick

If you touch the case and get a shock, release, and then touch again, do you
get another shock, and another? If you only get the one, then it is just
static and it's you that's 'electified' not the computer. I get this from
time to time, on both my desktop PC and my laptop - static 'belts' can be
really quite strong.

Rick

Electric shocks from computer case
 

"Richard Sterry" wrote in message ...
NickW wrote:
I've started getting electric shocks from the computer case.

If you touch the case and get a shock, release, and then touch again, do you
get another shock, and another? If you only get the one, then it is just
static and it's you that's 'electified' not the computer. I get this from
time to time, on both my desktop PC and my laptop - static 'belts' can be
really quite strong.

The real question is whether you still get a shock after the 100th
time. After 100 times you cant erally blame it on static any moer.
So.....?

No, dont really, it might be live for all I know :) Probably its
static discharge though.


Regards, NT