In article ,
David H-S wrote:
Another type of cable sometimes used c. 50 years ago for ring mains
consisted of a copper sheath, a ceramic insulator and then the live and
neutral leads inside that, cased I thinkk in rubber. The whole about
1/3 inch in diameter.
while lead cable was used for lighting in our house, this copper/ceramic
cable was used for the ringmain power crcuits in our old house. I think
it was installed in the late 50s for my parents.

What we saw by 2000 was increasing incidents of short circuits (via the
copper exterior) and blown fuses. Eventually whole circuits became
unusable. Regular slight movements, duw to floor boards & joists
flexing as people moved about, had caused the ceramic to crumble. then
maybe some damp penetrated and shorts were the result.

You've not understood MICC cable. The insulator is already a powder so
can't crumble.

If it was properly installed, it must have been damaged in some way and
let moisture in - that's the only thing that eventually kills it.

A totally different and longer lasting product than lead sheathed - and
indeed one which is still very much in use for hazardous applications.

--
*If at first you don't succeed, avoid skydiving.*

Dave Plowman London SW
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