I have used the IEC lead test to test an appliance that contains a double switched socket connected to lights and a dimmer switch that switches on a fan.

The O/C fault occurs when the polarity test is done. Am I using the correct test for this appliance?

A. The double sockets can be tested using the socket test, and the whole appliance can be tested by means of a Class I test. When performing this test all switches should be turned to their on positions. A continuity test will be done, followed by an insulation resistance test. As the Polarity test would not be included, the O/C fault would not be present.