Basic Electrical Installation Work

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410.Electrical installations and wiring systems 325 The British Standards Code Practice 1017, The Distribution Electricity on Construction and Building Sites, advises that protection against earth faults may obtained first providing low impedance path, that overcurrent devices can operate quickly described Chapter 12, and secondly fitting RCD addition the overcurrent protection device (IEE Regulation 704.313, 704. The supply usually provided a reduced voltage distribution unit which incorporates splashproof sockets fed from centre-tapped 110 transformer.75kW such cranes and lifts. The source supply for the temporary installation may from petrol or diesel generating set from the local supply company. construction site installation should be tested and inspected accordance with Part the Wiring Regulations every months throughout the construction period.3. This arrange- ment limits the voltage earth which recognized safe FIGURE 14. (a) (b) Safety First Construction sites ● low voltage or ● battery tools must used. ● 230 single phase for supplies items equipment which are robustly installed such floodlighting towers, small hoists and site offices. These supplies must wired in armoured cables.40 110 distribution unit and cable connector, suitable for construction site electrical supplies: (a) reduced-voltage distribution unit incorporating industrial sockets 60309 and (b) industrial plug and connector. ● 110 single phase for supplies all mobile hand tools and all mobile lighting equipment. The distribution electrical supplies construction site would typi- cally follows: ● 400 three phase for supplies major items plant having rating above 3. IEE Regulations 704. When the local electricity company provides the supply, the incoming cable must ter- minated waterproof and locked enclosure prevent unauthorized access and provide metering arrangements.8 tells that reduced low voltage strongly preferred for portable hand lamps and tools used on construction and demolition sites.10 and 411. .410. The 17th edition the IEE Regulations considers construction sites very special locations, devoting the whole of Section 704 their requirements. These supplies must wired armoured cable unless run inside the site offices.10).3