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sk1939
Premium Member
join:2010-10-23
Frederick, MD

sk1939 to tp0d

Premium Member

to tp0d

Re: [Electrical] New type of plug? or just BS

I've seen that before, and it's just a concept. It's also intended for Japan, as many Japanese outlets are two prong only, unpolarized still (there is a separate ground).

Msradell
Premium Member
join:2008-12-25
Louisville, KY

1 recommendation

Msradell

Premium Member

said by sk1939:

I've seen that before, and it's just a concept. It's also intended for Japan, as many Japanese outlets are two prong only, unpolarized still (there is a separate ground).

They also don't have the NEC which may claim to promote safety but in many cases just looks out for the interests of the manufacturers.

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

Jack_in_VA

Premium Member

+1

whizkid3
MVM
join:2002-02-21
Queens, NY

2 recommendations

whizkid3 to Msradell

MVM

to Msradell
said by sk1939:

It's also intended for Japan

said by Msradell:

They also don't have the NEC which may claim to promote safety but in many cases just looks out for the interests of the manufacturers.

Japan? The NEC? Yes, Japan does have the NEC.

They are only looking out for themselves. Its an evil manufacturing entity.

tp0d
yabbazooie
Premium Member
join:2001-02-13
Bulger, PA

1 recommendation

tp0d

Premium Member

said by whizkid3:

said by sk1939:

It's also intended for Japan

said by Msradell:

They also don't have the NEC which may claim to promote safety but in many cases just looks out for the interests of the manufacturers.

Japan? The NEC? Yes, Japan does have the NEC.

They are only looking out for themselves. Its an evil manufacturing entity.

bwahahah, good stuff

Subaru
1-3-2-4
Premium Member
join:2001-05-31
Greenwich, CT

Subaru to sk1939

Premium Member

to sk1939
said by sk1939:

I've seen that before, and it's just a concept. It's also intended for Japan, as many Japanese outlets are two prong only, unpolarized still (there is a separate ground).

I've always been curious where is the ground? I figured it was just ground on the body of the device but double insulated?

cybersaga
join:2011-12-19
Selby, ON

1 recommendation

cybersaga

Member

I poked around the internet. Apparently it's an outlet like this with a plug like this.

Subaru
1-3-2-4
Premium Member
join:2001-05-31
Greenwich, CT

Subaru

Premium Member

wow that's a hassle
iknow_t
join:2012-05-03

iknow_t to Subaru

Member

to Subaru
said by Subaru:

said by sk1939:

I've seen that before, and it's just a concept. It's also intended for Japan, as many Japanese outlets are two prong only, unpolarized still (there is a separate ground).

I've always been curious where is the ground? I figured it was just ground on the body of the device but double insulated?

the ground is through the unlucky human. it seems the Japanese like it that way..
54067323 (banned)
join:2012-09-25
Tuscaloosa, AL

54067323 (banned)

Member

said by iknow_t:

the ground is through the unlucky human. it seems the Japanese like it that way..

There is no ground because they don't use a neutral and because there are only two hots and neither of them is normally grounded or center-tapped to a grounded neutral there in no shock hazard present.

cybersaga
join:2011-12-19
Selby, ON

cybersaga

Member

said by 54067323:

no shock hazard present

I'm confused..... so if one of the two hots somehow shorted to the case of a computer, and you happen to be standing barefoot on a concrete floor and touched it.... nothing would happen?
54067323 (banned)
join:2012-09-25
Tuscaloosa, AL

54067323 (banned)

Member

said by cybersaga:

I'm confused..... so if one of the two hots somehow shorted to the case of a computer, and you happen to be standing barefoot on a concrete floor and touched it.... nothing would happen?

With no return path there is no shock, this is one of the advantages of an isolated secondary such as used in a number of countries.

tschmidt
MVM
join:2000-11-12
Milford, NH
·Consolidated Com..
·Republic Wireless
·Hollis Hosting

tschmidt

MVM

said by 54067323:

With no return path there is no shock, this is one of the advantages of an isolated secondary such as used in a number of countries.

One would think there would be enough unbalanced capacitive coupling to ground to create shock hazard even with no direct ground connection. One only needs enough leakage to cause a few milliamps to flow.

The other reason for Earthing the power distribution system is to bleed off static charge - do you know how that is accomplished in Japan?

Having been in Japan I can attest to the lack of three wire appliances but I'm not familiar with other aspects of their power distribution system.

/tom
alphageek911
join:2007-08-10
Fresno, CA

alphageek911 to 54067323

Member

to 54067323
said by 54067323:

With no return path there is no shock, this is one of the advantages of an isolated secondary such as used in a number of countries.

If one leg of a device on the line of that type of system gets grounded, wouldn't every other device on the line go hot? Not sure that seems safer....

Cho Baka
MVM
join:2000-11-23
there

Cho Baka to 54067323

MVM

to 54067323
Then how do they get 200V?

sk1939
Premium Member
join:2010-10-23
Frederick, MD

sk1939

Premium Member

said by Cho Baka:

Then how do they get 200V?

200V is very rare for the most part.
iknow_t
join:2012-05-03

iknow_t to 54067323

Member

to 54067323
said by 54067323:

said by iknow_t:

the ground is through the unlucky human. it seems the Japanese like it that way..

There is no ground because they don't use a neutral and because there are only two hots and neither of them is normally grounded or center-tapped to a grounded neutral there in no shock hazard present.

all it takes though is one house on your transformer to have a short to ground. frayed cord, shorted capacitor, wirenut that fell off, etc.

Jack_in_VA
Premium Member
join:2007-11-26
North, VA

Jack_in_VA

Premium Member

The circuit is "floating" above ground as the secondary of the isolation transformer is not grounded.
54067323 (banned)
join:2012-09-25
Tuscaloosa, AL

54067323 (banned) to iknow_t

Member

to iknow_t
said by iknow_t:

all it takes though is one house on your transformer to have a short to ground. frayed cord, shorted capacitor, wirenut that fell off, etc.

Yes and then they have any of the above connected to a source of power, but unless that appliance has a ground it is still floating.

Now there is the possiblity a mom could be standing on dirt, in the kitchen of her mud hut, touching her microwave oven with a short to the case, while her neighbor does the same, but other than that, there's probably not going to be a low enough resistance between two such moms in say a modern apartment building.


Cho Baka
MVM
join:2000-11-23
there

Cho Baka to sk1939

MVM

to sk1939
said by sk1939:

said by Cho Baka:

Then how do they get 200V?

200V is very rare for the most part.

Not where I was. Most apartments (mansions) had 200 V for the A/C units. The place I was in had it, and it was 20 years old.

sk1939
Premium Member
join:2010-10-23
Frederick, MD
ARRIS SB8200
Ubiquiti UDM-Pro
Juniper SRX320

sk1939

Premium Member

Which kind?





Cho Baka
MVM
join:2000-11-23
there

Cho Baka

MVM

Bottom table, fourth row down, third from the left.

sk1939
Premium Member
join:2010-10-23
Frederick, MD

sk1939

Premium Member

Good Overview of Japanese wiring: »rookie.h.fiw-web.net/him ··· 0421.htm