What is a Type F Schuko Electrical Plug Connector?

    Type F electrical plug (also known as Schuko – short for “Schutzkontakt” in German) for currents up to 16 A.

    It’s good to know about the Schuko plug, as it’s used in many electrical types of equipment, not just German products. In fact, most European appliances are equipped with such sockets. This F connector is used in Germany, Austria, Netherlands, Sweden, Finland, Norway, Portugal, Spain and Eastern Europe. Essentially the same Schuko devices are used in Russia and eastern European countries, except Poland, Czech Republic and Slovakia.

    Type F power plugs are known as CEE 7/4, colloquially known as “Schuko plugs”, an acronym for “Schu tz ko ntakt”, the German word for “protective contact” or “safety contact”.

    The original design of the safety, grounding plug and socket was the idea of Albert Büttner (Bayerische Elektrozubehör in Lauf). Patented in 1926. The plug has a grounding clip instead of a (third) grounding prong. Further development resulted in a version, which was patented in 1930 by Siemens-Schuckerwerke in Berlin. The patent describes a plug and socket still in use and known as the Schuko.

    Schuko is a registered trademark of SCHUKO-Warenzeichenverband eV, Bad Dürkheim, Germany.

    The plug was designed in Germany shortly after the First World War. It dates back to a patent (DE 370538) granted to the Bavarian electrical accessories manufacturer Albert Büttner in 1926.

    Type F is similar to the Type C plug, except it is round and adds indents with conductive clips on the top and bottom to ground the device. The plug isn’t perfectly round, but it has a pair of plastic notches on the left and right to provide extra stability when using large, heavy plugs such as built-in transformers.

    The Schuko F type plug has two 4.8mm round pins with a length of 19mm and a 19mm center-to-center spacing. The distance between either of the two ground clips and the midpoint of an imaginary line connecting the centers of the two power pins is 16 mm. Because the CEE 7/4 plug can be inserted into the receptacle in either direction, the Schuko connection system is non-polarized (ie line and neutral are connected randomly). It is used for applications up to 16 amps. In addition to this, the device must be permanently connected to the mains or via another higher power connector such as the IEC 60309 system.

    F-type Schuko plug connectors are fully compatible with Type E sockets, but this was not the case in the past. To bridge the difference between E and F sockets, a hybrid E/F plug (officially known as CEE 7/7) was developed. This plug is basically a common continental European standard for grounding, with grounding clips on both sides to mate with a Type F socket, and a female contact to accept the grounding pin of a Type E socket. The original Type F EU plug did not have this female contact, and while it is now obsolete, some DIY stores may still offer rewireable versions. Type C plugs fit perfectly into Type F sockets. The socket is recessed by 15mm, so there is no risk of electric shock from a partially inserted plug.