Japan overview of types of plugs and sockets

 

Japan uses flat blade plugs and sockets according to Japanese JIS 8303 standard. The 15 and 20 Amp types are similar to U.S. NEMA configurations. Domestic voltage in Japan is 100 Volt throughout the country; frequency is either 50 or 60 Hz, depending on the electric power company (click for details).

Related gallery: heavy duty types

Older sockets and plus - as no. 6 - have the old Japanese Industrial Standards mark (left). The Nihon Kongyou Kikaku mark, used since 2004 is shown at right.

 

1	Non-grounded duplex socket, rated at 15A - 125V. Japan follows the same code as U.S. for labeling neutral poles with W (white wire), rather than N. The socket has neutral (W) and line (hot) slots of different width. Image no. 3 shows the same socket. Manufacturer: National, a trademark of Panasonic Corporation for marketing home appliances in Japan. Bought in 2003.   {WaO}
2, 3	Adapter to provide an earth connection to a non-grounded socket. The horseshoe-shaped connector is attached to a ground connector hidden behind a plastic panel. The connector can also be used for appliance cords that have a two blade plug and a separate wire for grounding.   {WaO}
4	Grounded duplex socket, rated at 15A - 125V. In addition to earth pin slots the socket has a connection for a separate earth wire, identical to socket no. 1. Image no. 4 is based on a photo taken in Japan by Jonathan Miles. Manufacturer: National (Panasonic).
5	Connector, rated at 12A - 125V, with two outlets for non-grounded 15A plugs. The orientation of the blades is variable and can be rotated over 180 degrees. Made by an unknown Japanses manufacturer (see logo).   {WaO}
6, 6a	Non-grounded plug, rated at 15A - 125V. Plug is not polarized, because both blades have the same width. Blades have circular holes, a standard provision that helps to secure a plug when inserted in socket. Plug pins can be rotated over 180 degrees. Image no. 6a shows that a rotational movements is more easy to construct with plugs blades than round pins.   {DH}

7	Japan follows the North American pattern flat blade configurations for 15A-125V (left), 20A-125V (middle) plugs. The Japanese 20A-125V without earth connection (right) has an unique shape for the neutral (W) pin. Manufacturer: Meikōsha, Tokyo, Japan.   left and middle: {FSE};  right {FS}
8	Socket that accommodate both 15A and 20A - 125V grounded plugs (see image no. 7). In addition the socket has a provision to connect a separate earth wire (see image  nos 3 and 4). Socket is not part of the museum collection, but based on a photo taken by Jonathan Miles.

9	Duplex socket that allows locking of 15A, 125V plugs. Standard plugs can be used, but some plugs with a wider neutral (W) blade might be more difficult to lock/unlock. Manufacturer: National, trademark of Panasonic, used for domestic products.   {WaO}
10	Both plugs with and without ground pin can be used in combination with locking socket no. 9. The only condition is that the straight blades have holes (see arrows); a standard feature of both US and Japanese plugs. The locking principle is shown in image no. 11.
11	How it works: insert plugs in a diagonal position (left) and rotate it 30 degrees clockwise (right). In this position it is no longer possible to pull out the plugs, because vertical blade movement is stopped by balls that are now clicked into the holes. Plugs have to be rotated counter-clockwise for removal.
12	Grounded plug, rated at 15A - 125V. Plug has a flexible rubber housing to absorb shocks when falling. Plug is similar to U.S. NEMA 5-15P. Manufacturer: Meikōsha, Tokyo, Japan.   {FSE}
13, 14	Socket (13) and plug (14) rated at 15A - 125V with a U.S.-style twist lock mechanism. However these Japanese models are incompatible NEMA L5-15 plugs and sockets. Japanese plugs have a slightly different pin position and the earth pin does not have a hook. Manufacturer: National (Panasonic).   {DH}

15 - 18	Not grounded twist lock socket and plug for mounting on a ceiling. A (lightweight) lamp or pendant connector plug can be attached to the cable. The plug has to be rotated 35º to detach (16). Images 17 and 18 show the components separately. It is unlikely that the colours of the plug pin terminals indicate the neutral and line poles, because (i) the plug is symmetrical and can't be polarized and (ii) white and black are used for neutral and hot, although regional differences seems to exist in Japan. The National (Panasonic) type WG1000 ceiling connector set is rated at 6A - 250V. Bought in Japan in 2003.
19, 20	Multi-plug with two outlets for standard 15A-125V, not grounded plugs. The multi-plug has been designed for using in a bus bar; see image no. 21. The blades of the multi-plug are wider (7.9 mm rather than 6.3 mm), shorter (11.6 versus 17.0 mm) and thinner (0.75 versus 1.5 mm) and have neither a parallel nor tandem orientation. It is unknown for which type of socket the plug is meant. Trademark: National (Panasonic); type SD3939W. Bought in 2003.   {WaO}
21	Bus bar for domestic use. Earthed and non-earthed models exists. In both cases special plugs have to be used, as model SD3939W (unearthed, see images 19 and 20), or LC310 (earthed). National (Panasonic).

 

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