- Reaction score
- 8,783
I had an interesting little job this morning.
Three sockets in an extension were not working and haven't worked for quite some time (years).
It has perplexed a series of electricians. The last one was a friend of mine and invited me to have a look.
Flat roof above. Tiled floor. Ceiling had completely collapsed at some point and been repaired leading to suspicions of cable damage.
All 3 sockets had two cables running up towards ceiling.
No end-to-end continuity at the sockets.
The CU end of things:
My friend had already done some testing that he didn't find conclusive, so I decided to start again from first principles.
-Both main switches off.
-Take one of the non-working sockets completely off.
-Test both RFC's in top board, and both had perfect end-to-end continuity for all conductors.
-Conclude the circuit is nothing to do with two sockets circuits in top CU (unless the whole lot is a long spur which seemed unlikely)
-Refit the socket
So I look at bottom CU which was once for storage heaters (property now has central heating).
One circuit had two conductors though they are of different ages.
A quick test, and I could pickup L-E continuity at all three sockets
Same applied with L-N
Checked end-to-end at board and 0/3
Checked fuse - all fine.
So at this point I have an open-circuit ring or radial, suspicion that one of the legs in the board is actually nothing to do with it, no obvious location the far end of the circuit is going to, and the glaring question as to why the sockets weren't showing signs of life.
IR test of the working leg L+N to E = 10M. Good enough.
Check there is power at incomer, there is.
Which can only really leave one thing:
Yep, main switch not working.
My suspicion is:
-the sockets have always been a radial and there are one or more point(s) at the end of the circuit. (There's a new looking en-suite in the next room.)
-they should never have been in a 30 amp fuse in the first place.
-maybe the contacts of the main switch were deliberately removed when the central heating was installed?!
Anyway, the long overdue board change can sort all this out one way or another.
Three sockets in an extension were not working and haven't worked for quite some time (years).
It has perplexed a series of electricians. The last one was a friend of mine and invited me to have a look.
Flat roof above. Tiled floor. Ceiling had completely collapsed at some point and been repaired leading to suspicions of cable damage.
All 3 sockets had two cables running up towards ceiling.
No end-to-end continuity at the sockets.
The CU end of things:
My friend had already done some testing that he didn't find conclusive, so I decided to start again from first principles.
-Both main switches off.
-Take one of the non-working sockets completely off.
-Test both RFC's in top board, and both had perfect end-to-end continuity for all conductors.
-Conclude the circuit is nothing to do with two sockets circuits in top CU (unless the whole lot is a long spur which seemed unlikely)
-Refit the socket
So I look at bottom CU which was once for storage heaters (property now has central heating).
One circuit had two conductors though they are of different ages.
A quick test, and I could pickup L-E continuity at all three sockets
Same applied with L-N
Checked end-to-end at board and 0/3
Checked fuse - all fine.
So at this point I have an open-circuit ring or radial, suspicion that one of the legs in the board is actually nothing to do with it, no obvious location the far end of the circuit is going to, and the glaring question as to why the sockets weren't showing signs of life.
IR test of the working leg L+N to E = 10M. Good enough.
Check there is power at incomer, there is.
Which can only really leave one thing:
Yep, main switch not working.
My suspicion is:
-the sockets have always been a radial and there are one or more point(s) at the end of the circuit. (There's a new looking en-suite in the next room.)
-they should never have been in a 30 amp fuse in the first place.
-maybe the contacts of the main switch were deliberately removed when the central heating was installed?!
Anyway, the long overdue board change can sort all this out one way or another.
