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Background

I'm in China (hot, dry area) for the summer and am a guest in an old (1980s**) single family home. Because I am working all summer, I brought my desktop HP computer with me. After switching the desktop power supply from 115 to 230, I plugged it in and it works fine. Because the power drops /browns at least a few times per week, I have a UPS providing backup, allowing me to save my work and shut down in an orderly fashion.

The Problem

After a week or so, I noticed that I got a shock from the casing of my Desktop. I did some tests and notices that after plugging my pc after being unplugged for 8+ hours, it seems like:

  1. Before I turn it on in the morning, there is no static charge
  2. After 5+ hours, the charge is there but weak
  3. After a few days, the charge is stronger.

After some trouble shooting, I found that while the outlet has 3 prongs, as does all my equipment, the outlet ground is not connected to anything. Further, I went to the "fuse box" and saw that there was no grounded there either. So essentially the whole house is ungrounded.

I found this article to have a good summary of the problem, but the only work-around he suggested was to connect the chassis to the water supply. This won't work for me for two reasons, 1) The water is somewhat far away from where I work and 2) there is plenty of plastic pipes in the water system.

I have a GFI on the way, but I don't think this will resolve the problem.

Question

Right now, I am unplugging the computer when I sleep and at meal times, but this is a pain in the neck. Is there a work around besides connecting to plumbing?

For example, can I connect the chassis to a 5 gallon bucket (~ 20 L) filled with salt water? or filled with damp soil?

Note

** While most of the big cities in China with modern construction will follow some sort of electrical safety code, this house was built before the big boom, so it is a "3rd world" sorta house. And because I am a guest, it wouldn't be polite for me to re-wire the whole house (or neighborhood, for that matter).

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You might be able to make your own ground wire, provided you're near a window and on the first floor.

You'll need

  • A metal rod of some sort. Rebar might be commonly available. Doesn't have to be crazy long for these purposes, just has to stay in the ground
  • A clamp that fits around the metal rod
  • Some wire. Doesn't have to be a high gauge wire (18 gauge or so should work). If it's thicker than 16 gauge, make sure it's stranded and not solid.

Drive the rod into the ground by the window and fish some wire from inside to the rod and clamp it to that. Once that's done, take the other end and attach it to the case via a case screw (if you're using 18 gauge, just wrap the wire around a screw and re-tighten)

That should ground your computer (all computers ground to the case). All ground really is is an alternate path for excess electricity to flow to. That should alleviate the shocking problem you have. A GFI won't solve the problem because it's designed to detect an imbalance between the hot and neutral. It won't stop static buildup.

  • Will it work in dry soil too? For example, would this work in a place as dry as Las Vegas? – axsvl77 Jul 13 '17 at 3:57
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    Probably not. In dry-soil areas, like the desert southwest USA, the Ufer ground was created and tested which is grounding through the rebar in the building foundation footings. I doubt you can get to those. If you have exposed concrete flooring then running a bare wire under a damp cloth spread out on the exposed concrete could help dissipate the excess static. You could check in to vehicle anti-static straps. These are made of carbon impregnated rubber and used to dissipate static build up on vehicles when you stop. – ArchonOSX Jul 13 '17 at 7:34
  • If there is continuity from the desktop case to the wall outlet wiring and the entire house is wired "correctly" for a non-existent ground, wouldn't putting in an independent ground via a nearby window also ground the entire residence? – fred_dot_u Jul 13 '17 at 14:17
  • @fred_dot_u Good question. There are only two wires from the breaker to this outlet, and no conduit. They run through brick and concrete. So I think the ground for my desktop and the monitors and the UPS all share a ground, but nothing else. – axsvl77 Jul 13 '17 at 14:22
  • The independent ground should then protect you, without creating an unusual path for the rest of the house. +1 for the answer posted. – fred_dot_u Jul 13 '17 at 14:27
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Strange, a 1980's dwelling should have a grounding system in it. I would have you install a small plug in UPS around 850W. A UPS isolates the input from the output by creating it's own wave. It's also great for surge protection and prevents surges and brownouts. FYI do not connect up your printer to this system unless you upsize the UPS.

  • The location is China, enough said? – Ed Beal Jul 13 '17 at 21:03

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