P.R.Brady wrote:

Grant,
if it has 7 cores then it may be the old 7/029 standard. 7 cores,
0.29 something, and more tricky to work with than 2.5mm. 2.5mm came in
about the late 60s/ early 70s iirc. Yes it looks like a ring, yes I'd
just extend it with 2.5mm.
Phil


I'm pretty sure that it has six cores, but I'll check when I get home
tonight. However, based on other advice in the thread regarding full
circuit & earth loop impedence tests I think I will hand this job over
to a professional.

Cheers,
Grant