Basic Electrical Installation Work

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5/1. This test also verifies the polarity each socket outlet. ohmmeter reading should then taken between live and neutral every socket outlet the ring circuit.2. There are three steps this test.05Ω) the ring continuous. 14. 14.67 Step test: measuring the resistance phase, neutral and protective conductors.68.Basic Electrical Installation Work 354 The protective conductor resistance values calculated this method can only an approximation since the length the CPC can only estimated. The test made with the supply disconnected, using ohmmeter as follows: Disconnect and separate the conductors both legs the ring the main fuse.2 The object the test ensure that all ring circuit cables are continu- ous around the ring, that is, that there are breaks and interconnec- tions the ring and that all connections are electrically and mechanically sound. within 0.2. The protective conductor reading will 1. Therefore, this case, a satisfactory test result would obtained the resistance the protective conductor was about 0. Each reading should have value approximately Table 14.67 times as great these readings 2. 2 Testing for continuity ring final circuit conductors 612. Record the results a table such that shown Table 14. .5mm cable used. Step 1 Measure the resistance the phase conductors (L1 and L2), the neutral conductors (N1 and N2) and the protective conductors (E1 and E2) the mains position shown Fig. End-to-end live and neutral con- ductor readings should approximately the same (i.67.2 Test Ohmmeter connected to Ohmmeter readings This gives value for Step and r1 N1 and N2 E1 and r2 Step Live and neutral at each socket Step Live and earth at each socket R1 R2 As check (R1 R2) value should equal r2/4 L1 N2 Ohm- meter L2 L1 N2 N1 E2 E1 Ohm- meter FIGURE 14.e. Step 2 The live and neutral conductors should now temporarily joined together as shown Fig. more precise result indicated the earth fault loop impedance test which is carried out later the sequence tests.13 Table Which May Used Record the Readings Taken When Carrying Out the Continuity Ring Final Circuit Conductors Tests According IEE Regulation 612.6Ω. The readings obtained should substantially the same, provided that there are breaks mul- tiple loops the ring.13