Grounded outlets

[ketchupkatsu]

Is there some kind of rule against grounding electrical outlets in Japan?

I first thought that I was just in older buildings that is why no outlet is grounded, but the new building I'm in was built in 2007 and all the outlets are just the two prong types.

Has anyone else run into this situation or am I just unlucky?

[TennoChinko]

Is there some kind of rule against grounding electrical outlets in Japan?

I first thought that I was just in older buildings that is why no outlet is grounded, but the new building I'm in was built in 2007 and all the outlets are just the two prong types.

Has anyone else run into this situation or am I just unlucky?

Japan does have Type B grounded outlets, but they are less common than the two-prong Type As. You are more likely to find the former in offices than homes. At my place (built in the early 90's), we have both although the grounded outlets are mostly in the kitchen area.

I've seen electric 'power bars' for sale with grounded outlets and a two-prong ungrounded plug ... there's a spot to hook up a separate grounding wire.

[Coligny]

Is there some kind of rule against grounding electrical outlets in Japan?

I first thought that I was just in older buildings that is why no outlet is grounded, but the new building I'm in was built in 2007 and all the outlets are just the two prong types.

Has anyone else run into this situation or am I just unlucky?

Welcome to my misery...

The rule for grounding stuff in japan is to go against the safety laws of first-world countries. Take a green wire... tie it to a cold water faucet on one side, to your equipment on the other side. Rule is for mansion. If you have a house it might be easier to buy a copper rod (eiden/Kahma) burry it in the garden and bring the green wire to the house.

My actual house/mansion have fan coil central aircooling, I grounded 1 unit to the parking/garden now all the others can safely act as grounding plugs.

[Yokohammer]

In spaces where the washing machine is supposed to go, and sometimes in the kitchen for microwaves and whatnot, you'll sometimes find outlets with a ground screw under a little flap in the outlet cover.

However, I remember testing one of those ground screws in one of the places I lived previously, and ... you guessed it ... not grounded. Caution is advised.

Otherwise, the wider prong of the two-prong outlet (look at the slots ... one is longer) is supposed to be the ground side.

[Coligny]

Otherwise, the wider prong of the two-prong outlet (look at the slots ... one is longer) is supposed to be the ground side.

Wide / narrow game is to distinguish phase and neutral. Phase 1-phase 2 give you 200v, phase 1 neutral 1rst 100v circuit, phase 2-neutral give you the 2nd 100v circuit. Now for the earth-neutral relationship... by the book, i'd say yes. After seeing japanese electricians at work I'd say... find a good insurance company those guys don't understand even the start of what they are doing.

http://en.wikipedia.org/wiki/Split_phase

[IkemenTommy]

In spaces where the washing machine is supposed to go, and sometimes in the kitchen for microwaves and whatnot, you'll sometimes find outlets with a ground screw under a little flap in the outlet cover.

However, I remember testing one of those ground screws in one of the places I lived previously, and ... you guessed it ... not grounded. Caution is advised.

Otherwise, the wider prong of the two-prong outlet (look at the slots ... one is longer) is supposed to be the ground side.

I always wondered if those outlets were just for show and not properly grounded in the first place.

[Saru Paradise]

In spaces where the washing machine is supposed to go, and sometimes in the kitchen for microwaves and whatnot, you'll sometimes find outlets with a ground screw under a little flap in the outlet cover.

However, I remember testing one of those ground screws in one of the places I lived previously, and ... you guessed it ... not grounded. Caution is advised.

Otherwise, the wider prong of the two-prong outlet (look at the slots ... one is longer) is supposed to be the ground side.

Christ, I always just attached the grounding wire to the grounding screw assuming (apparently boneheadedly) that it was properly grounded. Why do you even have a tester for that lying around? I was content in my ignorance. I don't want to go buy surge protectors for everything in my apartment, nor do I want to try to finagle a connection to the AC ground (did you test that as well?).

[ketchupkatsu]

Just talked to Japanese electrical engineer, and this is his claim on why they mostly have only two prong outlets in Japan.

He states that the grounding prong is mostly to protect people from a short circuit in the equipment. Thus since Japanese equipment is built to be self insulated there is no need for an external ground, because any short in the equipment would not effect the user.

He said that is why you should always domestic electronics / electrical items, since any extra you pay for it is because of the extra quality they design into the product.

Don't know how much of this is true, but he has been working in the industry for years designing power tools.

[Number11]

Japanese devices do not use a plug with one wider prong. Only US plugs have that. They are both the same size in Japan.

The breakers in your house have ground fault protection, plus instantaneous over-current protection, so grounding at wall socket for consumer devices on single phase power isn't necessary.

Do some of you actually think that the people at Sony, Panasonic, Hitachi, Toshiba, Alpine, Fujitsu, NEC, TDK, Audio-Technica, Konica, Kyocera, et al don't know anything about electricity and grounding? That is incredible arrogance.

[ketchupkatsu]

Do some of you actually think that the people at Sony, Panasonic, Hitachi, Toshiba, Alpine, Fujitsu, NEC, TDK, Audio-Technica, Konica, Kyocera, et al don't know anything about electricity and grounding? That is incredible arrogance.

No I was just wondering out loud about the plug situation in Japan.

It just happened that I needed to do a presentation with a Sony laptop and a Toshiba projector and both had grounded plugs (laptop was purchased in Japan, the projector in the U.S.). Couldn't find a power strip or outlet in the center with a three prong ground and had to run out to a nearby Yodobashi camera to find an adapter (which even the clerk took a while to locate).

So I was wondering if there were building in Japan with grounded outlets, or if there were any regulations.

Sorry to have offended you Number11, I was asking not out of arrogance but out of curiosity.

[Number11]

Sorry, I wasn't really referring to you and your original question. Plus, I'm in a lousy mood. My apologies.

Grounded, three-prong outlets like in the US are rarely installed in Japan. The screw/ground type in some kitchens are there for old design high-resistance load appliances, but not really required these days with new designs. There are some in commercial buildings, but they are usually installed for a specific requirement.

[Tsuru]

Japanese devices do not use a plug with one wider prong. Only US plugs have that. They are both the same size in Japan.

The breakers in your house have ground fault protection, plus instantaneous over-current protection, so grounding at wall socket for consumer devices on single phase power isn't necessary.

Do some of you actually think that the people at Sony, Panasonic, Hitachi, Toshiba, Alpine, Fujitsu, NEC, TDK, Audio-Technica, Konica, Kyocera, et al don't know anything about electricity and grounding? That is incredible arrogance.

My (European Schuko-plug-) house has ground fault, over-current and lightning spike protection, and in addition to that all wall sockets are grounded.

Do you know what a ground loop sounds like on your brand new $2000, 16 gazillion watt amplifier?

Grounding is absolutely necessary. Everyone who works in audio, high-current motors or with anything at all that involves electricity at some point on land, sea or in the air knows this. It's a lot of fun troubleshooting devices with a disused ground connection which is floating all over the place.

[Coligny]

He said that is why you should always domestic electronics / electrical items, since any extra you pay for it is because of the extra quality they design into the product.

Don't know how much of this is true, but he has been working in the industry for years designing power tools.

Seriously... when engineers start to sound like soviet zampolit (political officers). You'd better hide your toolbox. I have yet to see a washing machine/ dish washer or even a gaz oven without grounding wire.

Japanese devices do not use a plug with one wider prong. Only US plugs have that. They are both the same size in Japan.

The breakers in your house have ground fault protection, plus instantaneous over-current protection, so grounding at wall socket for consumer devices on single phase power isn't necessary.

WTF ? If you live in the spaceship enterprise... (or in europe)... Yes that's true. In japan !? it's still the dark ages...

Do some of you actually think that the people at Sony, Panasonic, Hitachi, Toshiba, Alpine, Fujitsu, NEC, TDK, Audio-Technica, Konica, Kyocera, et al don't know anything about electricity and grounding?

I think they are more in the business of ridiculous cost cutting rather than any "state of the art" design. Not grounding electric equipment, with dry season as bad as it is, followed by high winds creating insane amount of static electricity buildups open you for a world of pain. My cats litterally glow in the dark when I pet them in winter. Same for the ungrounded computers.

That is incredible arrogance.

Another bigfoot troll... should have known...

[FG Lurker]

My cats litterally glow in the dark when I pet them in winter. Same for the ungrounded computers.

You pet your computers?