Basic Electrical Installation Work

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Definition Earthing the connection the exposed conductive parts an electrical installation the main protective earthing terminal the installation. fuse or MCB would meet this requirement. To provide overcurrent protection necessary provide device which will disconnect the supply automatically before the overload current can cause rise temperature which would damage the installation. Definition To provide overcurrent protection is necessary provide device which will disconnect the supply automati- cally before the overload current can cause rise temperature which would damage the installation. Figure 6. addition, means of switching off for maintenance emergency switching must provided. Earthing the connection the exposed conductive parts electrical installation the main protective earthing terminal the installation. An isolator mechanical device which operated manually and is provided that the whole the installation, one circuit one piece of equipment may cut off from the live supply. . Circuits are controlled switchgear which assembled that the circuit may operated safely under normal conditions, isolated automatically under fault conditions, isolated manually for safe maintenance. (IEE Regulation 131. The switch- ing electrically operated equipment normal service referred as functional switching. For current flow there must difference potential between two points, but the points are joined together there can potential difference. Let now define some the important new words they apply elec- trical installations. Definition The switching electrically oper- ated equipment normal service is referred functional switching.1). Protective electrical bonding earth The purpose the bonding regulations keep all the exposed metal- work installation the same earth potential the metalwork the electrical installation, that currents can flow and cause electric shock. A switch may provide the means isolation, but isolator differs from a switch that intended opened when the circuit concerned not carrying current. Its purpose ensure the safety those working the circuit making dead those parts which are live normal service. This bonding linking together the exposed metal parts of an installation known ‘protective equipotential bonding’ and gives protection against electric shock. One device may provide both isolation and switching provided that the charac- teristics the device meet the Regulations for both functions.Basic electrical circuits and cables 131 enclosures, earthing and bonding metal work and providing fuses cir- cuit breakers that the supply automatically disconnected under fault conditions.6 shows the connections and equipment domestic service position.1. The equipment belonging the supply authority sealed prevent unauthor- ized entry, because connection were made the supply before the meter, the energy used the consumer would not recorded the meter. Definition Bonding the linking together the exposed extraneous metal parts of an electrical installation for the pur- pose safety. Definition An isolator mechanical device which operated manually and is provided that the whole the installation, one circuit one piece of equipment may cut off from the live supply. Bonding the linking together the exposed extraneous metal parts of an electrical installation for the purpose safety. These requirements are met good workmanship carried out competent per- sons and the installation approved British Standard materials such as switches, isolators, fuses circuit breakers. fuse or MCB would meet this requirement