Museum of Plugs and Sockets logo, small Uncommon CEE 7/6 models
for specific purposes
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In Poland, one of the five countries in Europe that have adopted the French standard, two electrotechnical companies have developed special models of CEE 7/5 - 7/6 sockets and plugs. They are meant for local networks for equipment that is especially sensitive to power spikes and surges (computers etc.), or  installations requiring restricted access. Standard CEE 7/6 plugs do not fit in such special sockets, and vice versa. The Museum is grateful to Wojciech Maciak who has collected the plugs and sockets shown below.

An uncommon French 3-pin plug for extra low voltage applications is shown at the bottom of the page.


Polish DATA type E socket  
Polish non-standard DATA KEY type E socket Polish non-standard type E socket
Polish non-standard type E plug Keys for Polish non-standard type E plugs Polish non-standard type E plug Polish non-standard type E plug

1, 4 Non-standard  16A-250V DATA socket.The line slot (green arrow) has a triangular guide (see inset) that prevents the insertion of a standard plug. Only plugs with a corresponding notch - also indicated as mill-cut plugs - can be used, see image no. 4. Mill-cut plugs fits also in standard CEE 7/5 sockets. 
Line and neutral slots of the DATA socket are protected by a safety shutter. Socket and plug have been made by ELDA-FORUM, a Schneider Electric Polska company.
Note that this type of plugs and sockets comply the Polish national standard but don't seem to be really widely used.
The Museum is very pleased that it has been possible to trace the manufacturer for these devices.
2 Another type of non-standard socket made by ELDA-FORUM. The DATA KEY socket has two additional slots. Pins have to be inserted into these slots to open the blue safety shutters. Image no. 5 shows the key to open the shutters. Shutters can't be opened by line and neutral pins.
3 Comparable non-standard socket with a single additional slot to open the shutters. This type has been developed by the Polish company Kontakt, a part of the Spanish Simon Group.
5 - 7 Two blue, plastic keys, necessary to use DATA KEY socket nos. 2 and 3. Keys are provided with double sided self adhesive tape to glue them to standard CEE 7/6 plugs. The ready to use result is shown in image nos. 6 and 7.


Besides the Polish plugs and sockets shown above, also the Italian brand VIMAR offers a CEE 7/5 variant.
Note that you will not find CEE 7/5 - 7/6 standard sockets and plugs in Italy, because the country has its own, non-compatible, plug standard (see  CEI 23-50 page).

VIMAR non-standard type E socket VIMAR non-standard type E plug    

8 VIMAR type E 16A, 250V socket for the insertion of special purpose plugs. The slots of this socket have a special type of safety shutter. It can only be opened by a blade positioned between the pins of a tstandard CEE 7/5 plug. See inset below. The pins of a plug without this device can't push the shutter aside.   {WeO}
9 Standard type plug and device to open the safety shutter of a special VIMAR socket. The device also fits on French / Schuko hybrid plugs: CEE 7/7 (earthed) and CEE 7/17 (non-earthed). Devices come with the socket, but are also sold separately.

Legrand 3-pin ELV plug

Comparison of Legrand 2- and 3-pin ELV plugs

10 Extra low voltage (ELV) 3-pin plug made by Legrand. No. 76153 is now replaced by no. 050005, a 2-pin version (see image 11).
Such ELV plugs are, among others, used in French hospitals for calling a nurse.
The cord of the "attention button" is connected to an ELV relay that switches on an acoustic alarm and indicator lights.
Thanks to Michel Lagravere for clarifying the use of this type of ELV plug.
11 Three examples of the Legrand Arteor series. Each plug is unique because of differences in pin spacing and diameter.
Both 2-pin plugs are still in production (2022). The 3A 2-pin ELV plug is not a part of the museum collection.


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