Basic Electrical Installation Work

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2. Methods and are limited special situations under the effective super- vision trained personnel.1.3. In Chapter the IEE Regulations are told that where the metalwork of electrical equipment may become charged with electricity such a manner cause danger, that metalwork will connected with earth so discharge the electrical energy without danger. . the provision non-conducting location, 4. Method the use Class insulated equipment limited single pieces equipment such tools used construction sites, because it relies upon effective supervision ensure that metallic equipment or extraneous earthed metalwork enters the area the installation. this way the possibility voltage appear- ing between two exposed metal parts removed. Method electrical separation, little used but does find application in the domestic electric shaver supply unit which incorporates isolating transformer. These are: 1. The application of protective equipotential bonding one the important principles for safety. The method which most universally used the United Kingdom is, therefore, Method protective equipotential bonding coupled with auto- matic disconnection the supply. the use Class (double insulated) equipment, 3. the use earth free equipotential bonding, 5.2) achieved connecting exposed conductive parts equipment to the main protective earthing terminal.2 tells connect the extrane- ous metalwork water service pipes, gas and other service pipes and ducting, central heating and air conditioning systems, exposed metallic structural parts the building and lightning protective systems the pro- tective earthing terminal. Not only must all the metalwork associated with the electrical installation connected, that conduits, trunking, metal switches and the metalwork electri- cal appliances, but Regulation 411. There are five methods protection against contact with metalwork which has become unintentionally live, that is, indirect contact with exposed con- ductive parts recognized the IEE Regulations. protective equipotential bonding coupled with automatic discon- nection the supply, 2.7 Chapter 6. This method relies upon all exposed metalwork being electrically con- nected together effective earth connection. 6.Basic Electrical Installation Work 236 Fault protection Protection against indirect contact, called fault protection (IEE Regulation 131. electrical separation. Protective equipotential bonding shown Fig