CEE 7 standard AC plugs and sockets

First published in 1951 by the former International Commission on the Rules for the Approval of Electrical Equipment (IECEE), it unified standards produced by several continental European countries.

[1] The International Commission on the Rules for the Approval of Electrical Equipment (IECEE) was a standards body which published Specification for plugs and socket-outlets for domestic and similar purposes as CEE Publication 7, known simply as CEE 7.

In Germany unearthed sockets are rare, whereas in the Netherlands and Sweden it is still common to find them in "dry areas" such as in bedrooms or living rooms.

The socket (which is often, in error, also referred to as CEE 7/4) has a predominantly circular recess which is 17.5 mm (0.689 in) deep with two symmetrical round apertures and two earthing clips on the sides of the socket positioned to ensure that the earth is always engaged before live pin contact is made.

The Schuko connection system is symmetrical and unpolarised in its design, allowing line and neutral to be reversed.

The current German standards are DIN 49441:1972-06 "Two-pole plugs with earthing-contact 10 A 250 V≅ and 10 A 250 V–, 16 A 250 V~" (which also includes CEE 7/7 plug) and DIN 49440-1:2006-01 "Two-pole socket-outlets with earthing contact, 16 A 250 V a.c." In addition to Germany, it is used in Albania, Austria, Belarus, Bosnia and Herzegovina, Bulgaria, Chile, Croatia, Denmark, Estonia, Finland, Georgia, Greece, Hungary, Iceland, Indonesia, Iran, Italy (standard CEI 23-50), Kazakhstan, Latvia, Lithuania, Luxembourg, North Macedonia, Moldova, the Netherlands, Norway, Pakistan, Peru,[5] Portugal, Romania, Russia,[6] Serbia, Slovenia, South Korea, Spain, Sweden, Turkey, Ukraine, and Uruguay.

Some countries, including South Korea, Portugal, Finland, Denmark,[7] Norway and Sweden, require child-proof socket shutters.

[clarification needed] The CEE 7/5 socket and CEE 7/6 plug are defined in French standard NF C 61-314 "Plugs and socket-outlets for household and similar purposes" (which also includes CEE 7/7, 7/16 and 7/17 plugs) The socket has a predominantly circular recess which is 15 mm (0.591 in) deep with two symmetrical round apertures and a round 4.8 mm (0.189 in) earth pin projecting from the socket such that the tip is 23 mm (0.906 in) beyond the live contacts, to ensure that the earth is always engaged before live pin contact is made.

Although the plug is polarised, CEE 7 does not define the placement of the line and neutral and there is no universally-observed standard.

However, the Czech and Slovak standards defined that the earth pin should be at the top, if no special reason against, and the line wire had to be on the left side when facing the socket; those requirements are abandoned now.

The CEE 7/16 unearthed plug is used for low power Class II applications, it has two round 4 by 19 mm (0.157 by 0.748 in) pins, rated at 2.5 A.

Alternative II, popularly known as the Europlug, is a flat plug defined by Cenelec standard EN 50075 and national equivalents.

[8] To improve contact with socket parts the Europlug has slightly flexible pins which converge toward their free ends.

[9] Other than such personal hygiene applications, UK consumer protection legislation[10] does not permit Europlugs.