Lighting

[Bernardo]

We had an overflow of water last night which ran down to the toilet below right through the ceiling light switch and onto the bulb.
This morning I have replaced the ceiling rose with a new one and when I switch the mains back on the light comes on OK but will not go off.
I have checked the wall switch by swapping with one from another room and that is ok.
I have 3 red wires, 2 black and a single black going into the rose.
I made a note before I started of these so am certain they are back OK.
I can only think now that the water must have got into a junction box in the ceiling and wonder if I wait will it sort itself out
Any other bright ideas please

 

[Qedelec]

Yes! you have mixied up the cable in the ceiling rose.
Look at the Ref section for how a ceiling rose should be wired.
You have most likely transposed the switch wire with the live feed, I'll lay money that there is another ceiling light that doesn't work as well.

 

[Bernardo]

No I thought of other lights and all are fine.
I also am certain that the wires are exactly as they were.
All the reds to one port ,the 2 blacks which were together (still entwined) to another port and the final black(earth) on its own.
I taped the earth prior to removal to keep it separate.

 

[Qedelec]

No I thought of other lights and all are fine.
I also am certain that the wires are exactly as they were.
All the reds to one port ,the 2 blacks which were together (still entwined) to another port and the final black(earth) on its own.
I taped the earth prior to removal to keep it separate.

Err! final black(earth) What book are you reading that says black is earth.

 

[Bernardo]

Not reading a book but as it was wired to the earth connection on previous rose I took it that it is an earth but happy to be corrected.Whatever it is it was on its own before and is still on its own.

 

[Qedelec]

Not reading a book but as it was wired to the earth connection on previous rose I took it that it is an earth but happy to be corrected.Whatever it is it was on its own before and is still on its own.

Perhaps reading would be a good idea
You will usually have 3 twin and earth cables
One is the L & N in
One is the L & N out
And the other is the switch cable.
Identify which is which and wire according to the diagrams in the reference section.