Should My Computer Be Earthed ?

[Thetyim]

I recently moved house and my computer chassis now gives me a shock when I touch it. Maybe shock is too strong a description lets call it a tingle.

The chassis will light up a test screwdriver neon but will not give a reading on an AVO meter.

I took it into the computer shop but the problem disappeared when I got there and reappeared when I got it all back home.

The computer is working fine, should I just earth it, or look for something else.

If the problem is in the house supply, as it appears to be, then how does it get to the chassis ?

[Axel]

Yes!

I had the same and understand one neighbour in th house, who's computer is in a same room/position got shocks as well.

Turned out to be the A/C-unit outside the window but just 1/2 meter away. One cable from the unit to earth the connection solved the problem.

Was a bit of work so, had to drill a hole through the window frame.

[Guest timbee]

In order to answer this question, you must first perform the Glow Test. This will determine the extent of your Earth's problem. Perform the following easy steps:

1. Remove your clothing and attach a suitable bodily extremity to your computer chassis, e.g. your foreskin

2. Turn out all the lights

3. Remove all your girlfriend's clothes (or ask her to if your position in the puter chassis doesn't permit this)

4. Touch the most sensitive part of your gf's body with another of your extremities (I'll leave the choice to you)

5. If she becomes fidgety and giggles and visibly lights up, your Earth ain't half in a state and you need some assistance ...

6. Give gf some assistance first - she needs it most and her gratitude is nicer than the puter's

After this has all been done, you have two options:

A. Rewire the entire house; your puter has already gone phut and your gf's vibro may be the next to go

B. Drive a metal stake into the foundations of the house and wire the fusebox to it. Alternatively, if you can connect to a bit of steel reinforcement in the wall by driving a nail deep enough, skip the stake, and instead just run an earth wire from the chassis of the puter to the nail.

Works for me!

Readers with no electrical experience are sincerely advised to think twice before you take my advice.

Now do the Glow Test again

[astral]

The problem can sometimes be cured by simply reversing the power plug in the socket.

However the best way is to earth everything.

When I had my house rewired I requested 3 pin sockets throughout.

For you computer room, connect a wire to the earth pin of the extension board that you use for connecting the CPU, Monitor etc. Run the wire out of the window to a metal stake that goes at least 50cm down into the ground. This should provide you with a good earth.

[exchange1973]

Hi there,

use a potential equalization for your equipment. Unusual for home use but I think in your case it should be done. Things can get worse when you connect to machines over RJ45/twisted pair over a certain distance. If the two machines have not the same 'ground' (some volts are enough) the networkdevices will rest in peace.

In pro-environment a potential equalization is required.

Regards and greetings from cold Berlin!

exchange1973.

[Thetyim]

Thanks for the advise Timbee.

The glow test did not give consistent results so I tried again with the girl next door. The Gf then lit up and blew a fuse.

She then potentially equalized my equipment in accordance with the instructions from Berlin

Finally I connected a bit of wire from the computer chasssis to an adjacent metal water pipe and the problem has gone away.

Thanks for your replies

[lopburi3]

You have been given good advise (not all electrical).

By all means ground your computer (this will also ground anything attached to it like printer/scanner/modem via their connection cable so be careful if you touch this unit and your computer with the connection cable (USB) removed. This should take care of the shocks and clean up modem noise problems but it would be better to use the built in ground plugs of each piece of equipment as below.

If your home/apartment has ground (3 pin) outlets the best thing would be to buy real grounded outlet strips and use the built in plug grounds. You could also buy an outlet strip and run ground wire from it to a ground rod if home does not provide grounded outlets.

For serious protection (still get a shock) highly recomment you arrange for a GFI/RCD type device to protect your house/apartment. The 50 amp model Safe-T-Cut sells for about 4,000 baht installed and could save your life. Might even get landlord to pay for it.

[ASIC]

Just be careful. If your computer is earthed and the rest of the equipment is not, you could burn some chips (most likely in the computer) when you plug and unplug the devices. I suggest you earth a 3-pin extension cable through the metal pipe, and connect all your devices and computer to the now earthed extension cable.

ASIC