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So I am living in an apartment. This apartment is kinda old so it does not have the ground contact (Every electric outlet in this building comes out in 2 sockets only - no ground). I have a running desktop PC. Since there is no ground plug I have to use an adapter to convert the 3 prongs of PSU into 2 prongs on wall socket. This apparently gives my PC static shock whenever I touch on the metal part. A friend of mine gave an advice of hooking a wire from a screw bit of the PC, the other end wrapping around a nail punched into the brick wall. Assuming doing this would get rid of the static shock in my PC, would I get shocked (or any serious injury) if I (accidentally) touching the wire, or the nail end ?

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  • never assume anything ... it would only work if the nail contacts a grounded object
    – jsotola
    Nov 20, 2021 at 19:58
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    If that wire is a ground you would have to make contact with it and connect to a ground like your adapter or install a 3 wire receptacle) In the U.S. code changed a few years back allowing tapping a ground if it was connected to the source of the power (at the main or within 5’ of entry to the building if a water pipe) there are rules for the connection but just putting a nail l in the wall close won’t work.
    – Ed Beal
    Nov 20, 2021 at 20:42

4 Answers 4

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Touching the wire placed in the brick wall will do nothing, as will the entire wire. It's safe because it's also ineffective.

To do better: you could in theory run a wire from a nearby metal cold water pipe. Start with one of these: pigtail two to three prong grounding adapter japan

Then run an extension wire to a nearby cold water pipe, and use one of these:

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Or speak with your landlord about paying for an electrician to do what amounts to the same thing.

The third prong can help dissipate nuisance static, and it helps the surge protection equipment in your power strip or PC work better. It has little impact on safety in this particular case. Note that a GFCI device would solve no actual problem, though an electrician might want to install one because it easier than running a wire.

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  • 1) OP's concern is static, why do you write that brick is ineffective? ESD mats are not copper either. 2) GFI protects the user in the event of a fault and a loop through the user and ground, which is what one of the hazards is. This is not uncommon in isolated setups.
    – P2000
    Nov 20, 2021 at 21:08
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Static electricity always is an instant shock and then nothing, and it won't repeat unless you get up and walk around. Any shock which repeats or sustains is AC mains voltage trying to kill you.

Just because of the way electrical resistance works, most of the time you will feel it but it won't be able to flow enough current on a route through your body that would kill you.

Why is AC mains trying to kill you? Faulty PSU in the Poor auxiliary equipment (monitor, router, printer). Most PSUs (especially in 230V-land) need to be built so either wire can be "live". That is because most European sockets are reversible - flip them over and the other wire is live. But making PSUs safe also makes them more expensive.

A quality PSU should entirely isolate you from mains power, so it will not zap you. You will still get zapped by static electricity. Nothing will fix that.

There are two workarounds.

  • Use a RCD/GFCI protector of some kind. That will disconnect both live and neutral wires if you are starting to be electrically shocked. That will also shut off the computer, though.
  • Establish proper safety earthing. And there is a Codebook standard for doing that, and don't do anything less. Unfortunately many 5-continent installations depend on the utility to provide safety earthing.

Trying to do earthing "halfway" is counterproductive. If you aren't doing your earthing correctly, then you may be making things worse. If your computer is shocking you, then attaching that to a water pipe that isn't properly earthed is only going to make that water pipe shock anyone who touches it!

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A nail in a wall is not an Earth [or Ground depending on where you live]. A dry internal wall is just not a route to Earth.

An Earth is at minimum, a long heavy metal spike driven into the actual [physical dirt] ground, to which all Earth/Ground connections are bonded. The main Earth in compulsory Earth territories actually runs back to the local electricity sub-station on the main power grid.

A makeshift [& in compulsory Earth territories often used as a backup, but not only] Earth connection is to bond all bare metal piping together & wire Earth connections to that bonding. This works to some extent because [& if] the pipes actually run though the physical ground before they enter the property.
This only works at all if the piping to the property isn't plastic.

I would consult an electrician & not trust to guesswork or hearsay.

Note that even if your computer casing was correctly earthed, you could still get a static shock when touching it if you have plastic-soled shoes & nylon carpets [or rub a cat on an amber rod, or a balloon, or any of those old physics class experiments]. You would discharge your imbalanced potential to earth, using the ground connection & the case's propensity to act as a Faraday cage, protecting the computer's components.

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This is a trick and it can work well to dissipate static.

Since you are attaching the wire to the already exposed screw of the PC and not an internal wire, you are fine.

But note it will not provide adequate grounding as the PSU requires. If there is an internal short of some sort, the nail/wire will not provide a secondary high-current path to ground.

In situations like this it is safer to use an extension cord with built-in ground fault protection.

This will reduce the hazard. And you can still ground the PC with the wall/nail to dissipate static.

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