No power to upstairs lights...

[mikejacobs]

Tried replacing an upstairs light, which went a little wrong (sparks and things). Have tried to refit the old light (3 sets of black & red, switching wire identified), but none of the upstairs lights now work. Fuse doesn't trip out, and it is definitely a working fuse - any thoughts on what else could be the problem?

 

[mapj1]

Now you must assume that the wiring is not nececcesarily quite as standard as you hoped. Can you get into the loft above to see what goes where?
If not, as a first go, do all the other lights come on if you put all the reds together, all the blacks together and leave the switched pair out of use? If not then there is now a problem between fuse and this light. If all lights are off this must be the first fitting in the loop-chain.
Although the 'for reference' section shows the most likely arrangement, there is no absolute guarantee that you don't have a live black, or even a live earth core (sometime used with 2 way switches when there was not enough three core) clearly the use of the wires is not what you expect, but you know that already, the trick is to deduce what is really there

 

[mikejacobs]

OK - tried the direct connection, but nothing.

If the problem is between the CU and the lights, what can be done?

 

[mikejacobs]

Problem was a loose wire in one of the other light fittings. Now have power back in the upstairs ring (phew) but it appears to be transient. Still no luck getting the lights on - oh, and my earth wires are all live in one of the light fittings.

 

[plugwash]

given what you have just said (especially the earth wires being live) i think its time to get someone who has proper test equipment and knows how to use it

your wiring sounds VERY dodgy to me

 

[andy]

Problem was a loose wire in one of the other light fittings. Now have power back in the upstairs ring (phew) but it appears to be transient. Still no luck getting the lights on - oh, and my earth wires are all live in one of the light fittings.

are you sure the earths are live? fo they have a voltage between earth and neutral? also you dsy you have a multimeter. on the light you tried to change are any of the cables live?

 

[mikejacobs]

Thanks for all the advice - have decided that it is best to get an expert in!