Testing ground?

Hardware PSU
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So I am not electrician and dont know much about this stuff.

But I have drawn ground to my other room because I need to use UPS and I think UPS kinda likes ground…

So what I have done is that I bought some thick looking wire and screw the other end of that to my washing machine outlet and the other end to the loose wire of grounded power strip (here in Japan we have the strange looking ground wires hanging from every wire that needs grounding because we literally DO NOT HAVE GROUNDED OUTLETS HERE. For god forsaken reason I cannot understand.

So then this grounded “safe” power strip has my UPS hooked to it and to the UPS goes PC, monitor and Thinkstation S30 server.

But something makes me doubt how good the ground actually is.
I was thinking can I just buy some device like “ground tester” or test other way how “good” or “solid” or “lovely” the actual effect the ground has.

Something about this setup also makes me feel like this can be a hazard somehow.

I really really seriously want to move but my wife likes this location (too much) and is unwilling to move.

This being an apartment there isnt much to do except what I have done, bought 50Kg UPS that cost a lot and jerry rigged questionable wire from a washing machine socket to another room.

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There’s one way to know for sure - short it. If ocp pops it’s a good enough ground.

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I would hesitate to do that, I dont know if the system has GFCI style protection at all here.

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if the ocp does not pop… wouldn’t that cause a fire?

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Yes on the fire, so don’t keep the circuit closed for longer than needed to test.

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I’m no electrician but as i understand it ground is essentially just another path to neutral in case a live wire comes in to contact with the casing of a device. So I would think so long as you have continuity and low resistance between ground and neutral then your ground should be working. Though I’d be careful poking around in mains power. The best thing to do would be to get an electrician to come check things out if you’re having electrical problems.

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You should get an electrician. One thing your description of the terminations has me thinking the ocp may fail to function on a short to ground. Fault current handling of the equipment ground means machine threads in the terminations. Also things like wrapping only solid wire and in the right direction on terminal screws. Stranded wire goes in approved lugs and terminals.

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You could get an earth/ground tester, they are expensive tools with limited use though. Maybe there is a local place where you can rent one?

If you like fancy tools, installation testers can also do this. Price range is from Uni-T over Metrel to Fluke

Next problem is finding a known-good ground point like a metal gas pipe.

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I don’t know Japanese electrical systems and I am not a licensed electrician…so if I miss anything people please correct me.

If Japan electric is anything like US electric then you would have 220-240V coming in from a line transformer either on a pole or on the ground going to an electrical fuse/breaker panel.

Ground is achieved either though connecting a large wire to the water pipes of the dwelling or a literal large stake driven into the ground depending on the age of the structure and obviously if the pipes are metal or not then ground is connected to the neutral bus bars inside the electrical panel.

The 220-240V line is split to two planes each breaker connects to one of the hot lines coming in giving you the 110-120V to your outlet. 220-240V breakers take up 2 spots and connect to BOTH planes to give you the full 220-240V.

As for how things are wired to outlets…

Ground for non GFCI breakers to the outlets is achieved by connecting the neutral and ground wires to the neutral bus and hot to a breaker

Ground for GFCI breakers have the ground and hot connect to the breaker and it has a wire coming off the breaker as well as the neutral of the outlet you connect to the neutral bus.

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Japan is very much unique in that regard:

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The southern (western) half is 60Hz, the north (eastern) is running 50Hz, both at 100V.

AFAIK there is type A sockets (which lacks ground like the Europlug) and type B sockets, which are almost like grounded sockets in the US.

That is AFAIK unique to the US, presenting “split-phase” to the average person.
In Germany, you often find 3-Phase power (400V) for your oven or cooker, but other than that, it is only found in industrial applications.

Earthing is where the fun begins!

  • In a TN-S setup, Neutral and Earth run along side each other to the substation where they are tied together to a central ground point

  • TN-C-S (= PME) Neutral and Earth are basically the same, which means a break in the Neutral to the substation transformer makes EVERYTHING live
    I think DIN VDE 0100-200:2006-06 calls for an additional earth conductor to work around the exiting problems of a Neutral breaking

  • TT, “multiple grounds”, your house has its own earthing-point locally

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