This diagram provides guidance for checking the continuity of ring final circuit conductors for compliance with Regulation 612.2.2.
This should be viewed as step two to the post: Checking the continuity of live and protective conductors.
- Ensure installation, or appropriate part of it, is securely isolated, and proved to be so, before proceeding.
- Cross-connect the incoming neutral conductor with the outgoing phase of the circuit, and vice versa.
- Measure the resistance phase to neutral and note the result which should be approximately half the measured value of the phase or neutral conductor measured separately (as in Step 1).
- Alternatively, the measured value at each socket-outlet should be substantially the same. This measurement would be (r1+rn) or (1 + rn)/4.
The next diagram from Megger shows how you can check the continuity of ring final circuits with no spur.