There is a specific sequence of tests that must be carried out on your new/modified circuit or circuits. The first four tests are dead tests (Done before the circuit is energised). The results must be satisfactory before the circuit is switched on. If any tests fail, the problem must be rectified and the sequence of tests must be restarted. The order is as follows:

1. Continuity of the earth conductor in each new/modified circuit. (Dead Test)
2. Continuity of ring final circuit. (Dead Test)
3. Insulation resistance of each conductor. (Dead Test)
4. Polarity of switches and circuits. (Dead Test)
5. Earth Loop Impedance both at the origin of the installation and in the circuit. (Live Test)
6. Prospective Short Circuit Current (Live Test)
7. RCD trip time (Live Test)
8. Functional testing of all accessories in the circuit of circuits.

It is a requirement of the 17th Edition Wiring Regulations BS7671:2008 as amended that these tests are carried out before an installation is handed over to the end user.

Periodic testing is carried out in a different sequence as the circuit is already energised.