Installation Testing:Test of Polarity of Lighting Circuits

Test of Polarity of Lighting Circuits

This test must be done with the supply disconnected and may be carried out as follows: Remove circuit FUSE or open MCB. Remove all lamps from relevant circuit. Connect one end of the long trailing lead to the outgoing terminal of the circuit MCB. Using the other end in conjunction with the test meter leads, take readings from the phase terminal at all the points around the circuit e.g. switches and ES lampholders. Continuity ( approx. resistance of conductor involved ) at each point ensures that polarity is correct.

If the supply is disconnected from the installation the long trailing lead may be connected to the phase busbar and the MCB should then be left in the “on” position.