Ceiling light wiring issue

[joeninho]

Hi guys,

I am having a bit of a head scratcher while trying to fit a new ceiling light.

I made a schoolboy error in not taking a photograph before disconnecting the old light. I know, I know.

Anyway, there are two cables from the ceiling.

As far as I am aware, the the two live (red) wires should be wired together and put in a terminal block - not connected to the new ceiling light.

The two earth wires should be together and attached to the new light fitting.

Of the two remaining black wires, one is neutral and the other is the switched live. Needless to say, neutral to neutral and switch live to live in the ceiling light fitting.

Is that correct?

Unfortunately, I cannot tell which is which from the black wires. I have tried using a multimeter, yet it bleeps when testing both pairs of black/red wires.

To further complicate things, the light has two switches, one at the top of the hall stairs and one at the bottom. The switch at the top of the stairs does not work, although the light is working, as it switches on/off from the bottom switch.

Would this affect the continuity test?

Can anyone advise on how to identify the switch live? It is not identified by a brown sleeve or any other identifying mark.

A step by step guide would be hugely appreciated!

Thanks in advance,

Joe.

 

[Murdochcat]

You are fortunate only to have 2 cables so connect as you describe and it should be ok. If there is an issue when you switch it on the MCB or RCD Will instantly switch off the circuit (s)

Best that next time you do this please take a photo before you undo anything

 

[Jurassicspark]

Unfortunately, I cannot tell which is which from the black wires. I have tried using a multimeter, yet it bleeps when testing both pairs of black/red wires.

Black probe in one of the black wires and the other probe on the red wires. If you get 240V, then it's a neutral. If you get nothing then its a SL.

 

[SUNRAY]

Black probe in one of the black wires and the other probe on the red wires. If you get 240V, then it's a neutral. If you get nothing then its a SL.

The significantly quicker method would be a non contact device, such as a LED or neon screwdriver tester.