IR testing on lighting circuit, L-N split

[kingeri]

Looked at a job a few days ago, CU change. Customer showed me a mangled lighting circuit cable in the airing cupboard, it looked like it had been chewed up! Circuit still working and in regular use though. I IR tested circuit L-N and picked up no problem, which initially surprised me but then I realised that L and N are run in 'single and earth' and follow different routes around the house. The only points they converge are obviously at the lighting points. Hence, the test I did was useless. True?

L-E, N-E also did not show a problem, except for highlighting that the CPC has no continuity through the circuit!

Obviously, I'll replace the cable, just talking theory here.

 

[plugsandsparks]

Fair point, if they were damaged you may just get a higher reading L-E or N-E but they may just be exposed but not conducting to each other. Depends were the switch is in the cct as well, so need to IR with the switch on to cover all the cables