Testing polarity (regulation 612.6)
The term 'polarity' essentially means that we have got our wires the right way round, that is the lines in the line terminals, the neutrals in the neutral terminals and the protective conductors in the 'earth' terminals. Confirming correct polarity is a combined process of visual inspection, 'dead' testing and 'live' testing. During the initial verification of new installations, 100 per cent of terminations are visually inspected to ensure cables are correctly identified by colour or number and that each conductor is connected to its correct terminal. Polarity faults in the supply to an installation are not unheard of and can be extremely dangerous if not detected and rectified immediately. To verify the supply polarity, a series of measurements are made with an approved voltage indicator to confirm that the correct voltages are present at the correct supply terminals.