History AC power plugs and sockets: British and related types

bs 1363:1947 fused-plugs , shuttered socket-outlets resulted report post-war building studies no. 11, electrical installations

in 1941 lord reith, minister of works , planning, established committees investigate problems affect post-war rebuilding of britain. 1 of these, electrical installations committee, charged study of aspects of electrical installations in buildings. amongst members dame caroline haslett, president of women s engineering society , expert on safety in home. convened in 1942, committee reported in 1944, producing 1 of set of post war building studies guided reconstruction.

the plug , socket-outlet system defined in bs 1363 result of 1 of report s recommendations. britain had used combination of 2 a, 5 a , 15 a round pin sockets. in appendix main report (july 1944), committee proposed new socket-outlet , fused plug should adopted all-purpose domestic standard. main report listed 8 points consider in deciding design of new standard. first of these stated “to ensure safety of young children of considerable importance contacts of socket-outlet should protected shutters or other means, or inherent design of socket-outlet.” others included flush fitting, no need switch, requirements terminals, bottom entry cable, , contact design. appendix added 5 further points of technical detail including requirements plugs not inserted incorrectly, should easy withdraw, , should include fuse.

this requirement new system of plugs , sockets led publishing in 1947 of british standard 1363:1947 fused-plugs , shuttered socket-outlets .

one of other recommendations in report introduction of ring circuit system (often informally called ring main ). in arrangement cable connected fuse, or circuit breaker, in distribution board wired in sequence number of sockets before being terminated @ distribution board, forming ring final circuit. in ring circuit, each socket-outlet supplied current conductors on both sides of loop. contrasts radial system (which used in uk, in same installation) wherein single cable runs out radially, spoke, distribution board serve number of sockets. since fuse or circuit breaker ring circuit has rated maximum current ring carry (30 a or 32 a breaker), additional protection required @ each socket-plug connection. theoretically, such protection have been designated either within socket or within plug. however, ensure protection has rating matched appliance flexible cord fitted plug, fuse rated between 1 a , 13 a incorporated each plug. wired connections may connected ring, , these required include suitably rated fuse. ring circuit in uk requires use of bs 1363 plugs , sockets, bs 1363 system not limited use ring circuits.

chronology

an mk plug original version of standard. note unsleeved line & neutral pins, , inspection hole purpose of making connection of earth conductor visible cover in place (as required bs 1363:1947 clause 15.)

bs 1363 periodically revised, , supplements , amendments issued between major revisions. bs 1363:1984 , earlier versions dealt 13 a plugs , sockets. 1989 onwards standard rearranged 5 parts follows:

part 1: rewirable , non-rewirable 13 a fused plugs
part 2: 13 a switched , unswitched socket-outlets
part 3: adaptors
part 4: 13 a fused connection units: switched , unswitched
part 5: 13 a fused conversion plugs

the following chronology shows revisions, supplements , significant amendments.

june 1947: bs 1363:1947 fused-plugs , shuttered socket-outlets published.

may 1950: bs 1363:1947 amendment 3, title changed specification two-pole , earthing-pin fused-plugs , shuttered socket-outlets a.c. circuits 250 volts (not intended use on d.c. circuits) .

january 1957: bs 1363:1947 amendment 5, added clause permitting operation of shutters simultaneous insertion of 2 or more pins (in addition original method using earth pin).

january 1957: bs 1363:1947 supplement no. 1 added specification surface mounted socket-outlets.

1957: complementary standard published, bs 2814:1957 two-pole , earthing-pin flush-mounted 13-amp switch socket-outlets a.c. circuits 250 volts . separate standard specifying switched version of bs 1363 socket-outlet use bs 1363 plugs.

december 1960: bs 1363:1947 supplement no. 2, added specification resilient plugs.

december 1961: bs 2814:1957 amendment 2, title simplified 13 ampere switch socket-outlets .

1962: bs 2814:1957 supplement no. 1 added specification surface mounted switch outlets.

september 1967: bs 1363:1967 specification 13a plugs, switched , unswitched socket-outlets , boxes published. standard superseded both bs 1363:1947 , bs 2814:1957. 3 a , 13 a fuses specified. resilient plugs included.

august 1984: bs 1363:1984 specification 13 a fused plugs switched , unswitched socket-outlets published. standard superseded bs 1363:1967. changes include introduction of sleeved pins on line , neutral, metric dimensions replacing inches, specifications added non-rewirable plugs , portable socket-outlets. standard aligned, possible, proposed iec standard domestic plugs , socket-outlets.

february 1989: bs 1363-3:1989 13 a plugs socket-outlets , adaptors - part 3: specification adaptors published. new standard covers adaptors use bs 1363 socket-outlets , includes conversion adaptors (those accept plugs of different type), multiway adaptors (those accept more 1 plug, may or may not of different type) , shaver adaptors. adaptors (except accepting not more 2 bs 1363 plugs) require fused. sockets, including other standards, must shuttered.

1994: product approval specification, pas 003:1994, non-rewirable 13 a plugs plastic socket shutter opening pins published. pas 003 allowed design , approval of plugs without earthing intended class ii applications only. superseded bs 1363-1:1995 pas not withdrawn until 23 july 2013.

february 1995: bs 1363-1:1995 13 a plugs socket-outlets adaptors , connection units - part 1: specification rewirable , non-rewirable 13 a fused plugs published. standard, bs 1363-2:1995, supersedes bs 1363:1984. provisions of pas 003 incorporated, plastic pin redesignated isod

september 1995: bs 1363-2:1995 13 a plugs socket-outlets adaptors , connection units - part 2: specification 13 a switched , unswitched socket-outlets published.

september 1995: bs 1363-3:1995 13 a plugs socket-outlets adaptors , connection units - part 3: specification adaptors published. supersedes bs 1363-3:1989

november 1995: bs 1363-4:1995 13 a plugs socket-outlets adaptors , connection units - part 4: specification 13 a fused connection units switched , unswitched published. new standard.

august 2008: bs 1363-5:2008 13 a plugs socket-outlets adaptors , connection units - part 5: specification 13 a fused conversion plugs published. new standard.

may 2012: bs 1363-1:1995 +a4:2012 (title unchanged) published. amended standard allows switches incorporated plugs, , introduced new overload tests amongst others. bs 1363-1:1995 remained current until 31 may 2015.

may 2012: bs 1363-2:1995 +a4:2012 (title unchanged) published. amended standard adds requirement shall not possible operate shutter insertion of two-pin europlug, , introduced new temperature rise tests amongst others. bs 1363-2:1995 remained current until 31 may 2015.

may 2012: bs 1363-4:1995 +a4:2012 (title unchanged) published. minor changes bs 1363-4:1995 remained current until 31 may 2015.

november 2012: bs 1363-3:1995 +a4:2012 (title unchanged) published. amended standard adds requirement shall not possible operate shutter insertion of two-pin europlug, , added specifications switched adaptors amongst others. bs 1363-3:1995 remain current until 31 december 2015.

august 2016: bs 1363-1:2016 (title unchanged) published. added requirements incorporated electronic components , electric vehicle charging. bs 1363-1:1995 +a4:2012 remain current until 31 august 2019.

august 2016: bs 1363-2:2016 (title unchanged) published. added requirements incorporated electronic components , electric vehicle charging. bs 1363-2:1995 +a4:2012 remain current until 31 august 2019.

august 2016: bs 1363-3:2016 (title unchanged) published. added requirements incorporated electronic components. bs 1363-3:1995 +a4:2012 remain current until 31 august 2019.

august 2016: bs 1363-4:2016 (title unchanged) published. minor changes only. bs 1363-4:1995 +a4:2012 remain current until 31 august 2019.

august 2016: bs 1363-5:2016 (title unchanged) published. minor changes only. bs 1363-5:2008 remain current until 31 august 2019.