Electric Reference

note: To ensure the cables form a complete ring throughout and that every point is correctly connected in the correct polarity and has no interconnections

1. Safely isolate supply
2. Test continuity between the ends of the Line conductor and record value
3. Test continuity between the ends of the Neutral conductor and record value
4. Test continuity between the ends of the CPC conductor and record value
5. Join leg 1 of Line to leg 2 of Neutral
   Now test between leg 2 of Line and leg 1 of Neutral
Note: that the resistance will be double of the single line conductor
6. Now join both legs which you just tested from
   leg 1 of Line and leg 2 of Neutral joined
   leg 2 of Line and leg 1 of Neutral joined
Testing between the jointed legs should give a reading of a half of the line conductor
7. Leave ends joined as in step 6
8. Test at each socket of the circuit between Line and Neutral note: all readings should be the same

Readings which tend to higher may have incorrect polarity at one of the sockets, but further investigation should proceed.
10. Repeat step 10 using CPC and Line
   leg 1 of Line and leg 2 of CPC joined
   leg 2 of Line and leg 1 of CPC joined
Record results

note: If there are any spurs on the circuit, it will be more than likely that the readings of them are the highest, and these ones should be recorded for your r1 + r2