"Lobster" wrote in message ...
"N. Thornton" wrote in message
om...

You say the house has been rewired recently, but to be honest thats
hard to believe from the pics of the fusebox. Partial rewiring might
have been done, but the idea that someone managed to gain enough
access to that old fusebox is stretching it. And again, if they didnt
replace an old and inaccessible 4-way wire fuse only box, or even
upgrade it to mcbs, youve got to wonder what they were thinking.

You may be right - I can't remember (or find!) what I said about rewiring,
but it certainly wouldn't have been that
recent; I just meant that it was more recent than the fusebox suggests.

4 way Wylexes are typical 70s kit, and were widely installed in the
80s as well. Those old Wylexes arent as old as they first appear. In
the 70s they were partly wooden, and many people have misjudged their
age.

I
would certainly
guess that the gas meter was added later though.

ha, I hope so! If the leccy were added _sfter_ the gas there would be
more reason to worry


I certainly have lots of checking to do; I agree.

If it were mine I might start by checking resistance from house wiring
earth to real earth, as it would at least give a very quick idea of
how unsatisfactory things are. If R is high you would have a high risk
install there. If R is nice and low that would at least be reassuring
on that fairly major point.

What do you define as 'real earth' - are you refering to the incoming cable
sheath? Or an earth rod somewhere (which would be difficult as there's no
'soft' ground anywhere nearby.

Local earth rod, which you probably have in the form of an incoming
metal water mains pipe. Confirming low R doesnt mean all is well, but
it at least would eliminate the biggest possible risk of all, the lack
of any functional earth.

Unfortunately having an earth connection doesnt automatically imply it
will work as a safety feature. If earth R is too high, with no RCD the
fuse wires would sit there forever more before anything blows, with
the whole earth circuit live - but its not very likely to be anything
like that bad.


NT