Basic Electrical Installation Work

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The Health and Safety Executive has published Guidance Notes GS 38 for test equipment used electricians. this and comply with Regulation 612.2. d.Electrical installations and wiring systems 351 There increased use electronic devices electrical installation work, for example, dimmer switches and ignitor circuits discharge lamps. Approved test instruments The test instruments and test leads used the electrician for testing an electrical installation must meet all the requirements the relevant regu- lations.c. CONTINUITY TESTER To measure accurately the resistance the conductors electrical installation must use instrument which capable producing an open circuit voltage between and 24V a.c. Test instruments must, therefore, tested and recalibrated each year an approved supplier. Definition All testing must, therefore, carried out using ‘approved’ test instru- ment the test results are valid. All testing must, therefore, carried out using ‘approved’ test instrument the test results are valid. During the test, the instru- ment does Ohm’s law calculation and displays the test result resist- ance reading.3 the test instrument must capable of producing test voltage 250V, 500V 1000V and deliver output cur- rent not less than 1mA its normal voltage. INSULATION RESISTANCE TESTER The test instrument must capable detecting insulation leakage between live conductors and between live conductors and earth. The test instrument must also carry a calibration certificate, otherwise the recorded results may void. Definition The test instruments and test leads used the electrician for testing an electrical installation must meet all the requirements the relevant regulations., and deliver short- circuit current not less than 200mA (Regulation 612. . This will maintain the accuracy the instrument an acceptable level, usually within the true value. The functions of continuity testing and insulation resistance testing are usually com- bined one test instrument.1).3). Modern digital test instruments are reasonably robust, but maintain them good working order they must treated with care. All test equipment must chosen accordance with the relevant parts 61557. Let look the requirements four often used test meters. The test instrument must also carry calibration certificate, otherwise the recorded results may void. The IEE Regulations (BS 7671) also specify the test voltage current required carry out particular tests satisfactorily. approved test instrument costs equally much good-quality camera; should, therefore, receive the same care and consideration. These devices should temporarily disconnected that they are not damaged the test voltage of, for example, the insulation resistance test (Regulation 612. EARTH FAULT LOOP IMPEDANCE TESTER The test instrument must capable delivering fault currents high as 25A for 40ms using the supply voltage. Calibration certificates usually last for year