I've done a bit of testing this afternoon, and found a fault on a ring
main.
Continuity results:
E-E 0.40 ohms
N-N 0.19 ohms
L-L 37 ohms - clearly a fault here.

I checked the 4 sockets on the ring for loose connections, and found no
apparent fault.
So next I joined up opposite ends of L+E, and measured R1 + R2 at the
sockets: 0.42 ohms, 0.42, 0.48, and 0.51ohms.

Clearly the resistance goes up as the sockets get further away.

Muddled thinking got me nowhere.
After a while, I was thinking that the cable must be damaged between the
final socket and the return cable.
But, a resistance of 37 ohms? That doesnt seem to be enough to be a
damaged cable.
(Insulation resistance was checked, and all fine at 1k M ohms)

Any thoughts?
Ta
Alan.

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