What are the Pulleys For?

Adaptors were available from 15 A down to 5 A and from 5 A down to 2 A so in practice it was possible for an appliance with the smallest size of flex to be protected only by a 15 A fuse. Fuses are mechanically interchangeable; it is up to the end-user or appliance manufacturer to install the appropriate rating fuse. In BS 546 there are no dimensions for socket contacts, instead they are required to make good contact with the specified plug pins. In the United Kingdom and in Ireland, this system is usually referred to simply as a "13 amp plug" or a "13 amp socket". In the United Kingdom and in Ireland this system is usually referred to by its pin shape and is simply known as "round pin plugs" or "round pin sockets". The system produced up to 1 kW of power at the receiver end. BS 1363, 13 A plugs socket-outlets adaptors and connection units is a British Standard which specifies the most common type of single-phase AC power plugs and sockets that are used in the United Kingdom.

By the time the 1911 GEC Catalogue was published two-pin plugs and sockets were being offered with specifications in amps, but still with no indication as to pin size or spacing. These were clearly recognisable as two-pin plugs and sockets, but with no indication as to pin size or spacing, they were sold as pairs. BS 4573 British Standard Specification for two-pin reversible plugs and shaver socket-outlets defines a plug for use with electric shavers. British Standards for plugs (with the exception of BS 4573) have always specified side entry flex (entry in other types is usually parallel to the axes of the pins). Following the introduction of BS 4573 in 1970 there were no longer any UK domestic uses for two-pin sockets except for shavers, so BS 372 was renamed "Two-pin Side-entry Wall Plugs And Sockets For Special Circuits" and subsequently withdrawn. SS 472:1999 15 A plugs and switched socket-outlets for domestic and similar purposes. This was despite almost nine in ten respondents admitting they're aware that the domestic extension leads should not be used outside - and over half saying they use them even when it's raining. There is no European Union regulation of domestic mains plugs and sockets; the Low Voltage Directive specifically excludes domestic plugs and sockets.

Digital Museum of Plugs and Sockets. The 15 ampere (A) sockets were generally given a dedicated 15 A circuit. Multiple 5 A sockets might be on a 15 A circuit, or each on a dedicated 5 A circuit. Generally the plug is the movable connector attached to an electrically operated device's mains cable, and the socket is fixed on equipment or a building structure and connected to an energised electrical circuit. BS 546:1934 clause 2 specifies interchangeability with BS 372 Part II which includes the same four plug and socket sizes. The insurance provider says it is the same sort of scenario as a customer putting the wrong fuel in their internal combustion engine car, what is electric cable with insurers covering these claims as accidental damage also. This plug was also once used in theatrical installations for the same reasons as the 15 A model below. The plug and socket replaced the BS 546 plug and socket, which are still found in old installations or in special applications. To reduce the risk of users accidentally touching energized conductors and thereby experiencing electric shock, plug and socket systems often incorporate safety features in addition to the recessed contacts of the energized socket. There were concerns that consumer safety was compromised by the substantial quantity of counterfeit and unsafe electrical plugs and sockets being placed on the UK market and also by the provision of electrical equipment without an appropriate means to connect it to the mains supply in the consumer's home.

In 1885, two-pin plug designs appeared and in 1889 there were two-pin plugs and sockets in the GEC catalogue. The 1911 General Electric Company (GEC) Catalogue included several earthed sockets intended for industrial use. When BS 546 was in common use domestically in the UK the standard did not require sockets to be shuttered, although many were. There are several common types, including double- and triple-socket blocks, shaver adaptors, and multi-socket strips. In some countries where electric locomotives or electric multiple units run on low frequency AC power, separate single phase traction power networks are operated by the railways. • Category 1 and 2 cables were originally used for voice communication with low data rates. T1 circuits, implemented over twisted-pair copper cables, are still in use today to carry voice channels over relatively short distances (up to 20 or 30 miles). Under this code, the highest cable in the communications space must be separated from the lowest electric-power conductor in the supply space by specified distances. The Communications Space contains telephone, cable television (CATV), and other communications cables. 1989: Pay Per View begins to leave its mark on the television landscape, reaching about 20% of all wired households.