AC power plugs and sockets - British and related types

With the British Connectors, Plug Type G and BS 1363, " british 3 -pin " or " Commonwealth Connector " is a product from the UK electrical connector system, in the field of electrical energy supply of households and general low voltage power applies. Its use is recommended in the United Kingdom.


The following countries use the British Connectors exclusively as a standard plug-in system or partly with other systems:

  • United Kingdom (exclusive)
  • Ireland ( exclusive)
  • Singapore ( exclusive)
  • Malaysia ( exclusive)
  • Botswana
  • Brunei
  • Ghana
  • Gibraltar
  • Hong Kong
  • Iraq
  • Jordan
  • Qatar
  • Kenya
  • Kuwait
  • Macao
  • Malta
  • Nigeria
  • Oman
  • Saudi Arabia
  • Seychelles
  • Uganda
  • United Arab Emirates
  • Cyprus

See: Overview of country plug types, voltages and frequencies


The design and specification of BS 1363 take on a special feature of the house wiring consideration, which is generally found only in the United Kingdom and several former British colonies. The cabling consists of one or more line rings per floor or per apartment, also referred to as a ring circuit. A power cable, starting out from the fuse box from outlet to outlet through the apartment and from the last socket back to the fuse box per ring. This feedback enables higher port values ​​at lower cable cross-sections ( a socket receives from both directions of the ring current). So that copper can be saved in the sum. Used to be only one ring per floor common, way was, for example, a ring per floor apartment and on to more rings per floor flat above, for example, an additional ring for the kitchen. Limited may be set by a ring stitch lines to individual sockets, but this is considered unclean. The in other countries such as in Germany, the usual star wiring is made by slowly.

BS 1363 was introduced in 1947, up to this point was BS 546 (Type D) standard. Of these, there are versions for 2, 5, 10 or more amps, with 5 A was used in households. Accordingly, the circuit also had to be fitted with a 5 A. As this was too little power (240 V x 5 A = 1200 W ) in the ring, it was decided to new wiring regulations. The aim was to secure a ring with 16 A, 20 A or 32 A at all, because one ring should be one to two electric heaters to 3000W each (equivalent to about 12.5 A per radiator ) and a number of smaller consumers can provide. Since the current of 32 A from a single outlet for a conventional device connection cable is too high and strong, bulky device connecting cables should be avoided, had backups to either be integrated into sockets or plugs. The plugs were fitted with fuses of either 3 A, 5 A or 13 A. To prevent the old, unhedged BS -546 connectors can be used in a 32- amp circuit, a new, incompatible socket standard was developed. BS 1363 was introduced in the UK in 1965 and sat down quickly. Similarly, it went in the other countries that use this standard. South Africa used to date a compatible plug to BS 546 standard. The old plug-in system is in the countries concerned in old installations from the period before 1965 and in special installations ( such as in theaters ) still to be found.


The British connector is defined in the British Standard BS 1363. The standard requires that this connector is provided always three-phase and with a fuse. The contact pins are rectangular. Phase conductor and neutral measure 4 × 6 × 18 mm; 9 mm of which are isolated. They have a distance of 22 mm. The earthing contact is located in the middle, with the two conductors at a distance of 22 mm. It is equipped with 4 × 8 × 23 mm longer (assuming haste ) as the live pins and without insulation. The live contact pins are polarized by the rotational asymmetry ( the outer conductor is always located on the right side of the socket or the plug in the plug ). The plug was widened at the site of contact pins to discourage touching the insulated not from the start contacts ( finger safe). There is also a recessed grip to facilitate withdrawal of the right stiff plug from the socket. The Standard also includes a child safety lock which closes the contact holes from the inside. It is released by the insertion of the grounding element. Plug for protection class II devices (protective insulation) have only a plastic pen instead of the protective contact.

Similar standard

The British Standard BS 1363 is similar to the Irish standard of NSAI IS 401 Safety Requirements for Rewireable 13A Fused Plugs for Normal and Rough Use Having Insulating Sleeves on Line and Neutral pins.


BS 1363 has the following security features:

  • Polarized / reverse polarity protected
  • Pretriggered protection Contact
  • Childlock
  • Isolated contacts / finger-safe
  • Fuse in the plug ( 3/5/13A )




Some manufacturers have developed variants of BS 1363. They are used where the insertion of standard connectors is either not desired or not recommended. Examples are electrical outlets in public buildings, which are necessary for internal use, but for which the unauthorized use is not wanted. The most common is a variant of MK electric with a T-shaped earth pin.

Sources and References

  • British Standards BS 1363: 13 A plugs, socket - outlets, Adaptors and connection units. Part 1: Specification for Rewirable and non- Rewirable 13 A fused plugs. BS 1363-1:1995.
  • Part 2: Specification for 13 A switched and unswitched socket- outlets. BS 1363-2:1995.
  • Part 3: Specification for the adapter. BS 1363-3:1989.
  • Part 4: Specification for 13 A fused connection units switched and unswitched. BS 1363-4:1995.