
Summary: Learn how to use a continuity tester to check a socket outlet.
A continuity tester is used to check that a socket outlet with two cables connected to it is connected to the ring main. Before installing a spur the socket must not already be supplied by a spur.

How to use a continuity tester
- Cut off the power supply to the relevant circuit from the consumer unit.
- Either remove the fuse protecting the circuit you will be working on or switch off the MCB (miniature circuit breaker).
- Unscrew the face-plate from the socket you want to test.
- Disconnect the two live cores (red).
- Clip the continuity tester onto the end of one core.
- Touch the other core with the probe.
- If the bulb on the continuity test is illuminated, the circuit has been completed and the socket is on the ring main and suitable to connect a spur to. If it fails to light up, it is already on a spur and cannot be used to supply one.
Important note:
The colour-coding system for electric cable changed in 2006, make sure you read Electric cable and flex to view the new information.