Light fitting wiring

[Taylortwocities]

Here's one you can actually see!

 

[John Jackson]

I have done this and established the wire with power which will be the switch?

 

[Taylortwocities]

Why are you looking for the power? You need to find the switch FIRST…..

Keep the fuse box off, and on continuity, test between a pair of red and blacks. Get a helper to operate the switch, once you get continuity with the switch on and don't with it off, that's your switch wire

 

[John Jackson]

I have done this with the wires switching the switch on and off and two of the wires read 1 and the other one would jump then drop jump then drop

 

[Himaginn]

You should be testing each pair of red and black.
So take one pair of the same T&E cable, test it as advised, if there is no difference, try another pair from a different T&E, if there is again no difference, try the third pair from the remaining T&E. One of those pair within one of the T&E cables will show a difference in reading with the switch on or off.
That is the pair going to the switch. The other two pairs are live and neutral, and go together.

The red of the pair that go to the switch also go with the other two lives, and the remaining black is the switch wire.

Only the neutrals and the switch wire are connected to your lamp.

 

[John Jackson]

Thankyou that makes it sound a hell of a lot easier

 

[Himaginn]

The other two pairs are live and neutral, and go together.

Just to clarify, in case you misunderstand, the lives go together, and the neutrals go together.

The lives you'll need to connect together somehow, usually with a connector, because I doubt you'll have the facility within your new lamp.

So you should end up with 3 red (2 lives and a live feed to switch) together not connected to your lamp, 2 blacks (neutrals) together connected to your lamp, and one black, which is the switch wire also connected to your lamp.

 

[John Jackson]

The other two pairs are live and neutral, and go together.

Just to clarify, in case you misunderstand, the lives go together, and the neutrals go together.

The lives you'll need to connect together somehow, usually with a connector, because I doubt you'll have the facility within your new lamp.

So you should end up with 3 red (2 lives and a live feed to switch) together not connected to your lamp, 2 blacks (neutrals) together connected to your lamp, and one black, which is the switch wire also connected to your lamp.

 

[John Jackson]

Is this diagram the right sort of thing?

 

[Himaginn]

Spot on!
You can't rely on testing for power because only one red will be live and you'd still be uncertain which goes to switch.

 

[EFLImpudence]

It very likely is spot on but ...

is there only one light in the room?

 

[Himaginn]

It very likely is spot on but ...

is there only one light in the room?

Excelent point EFLI. It needs answering:

but I have recently received a couple of light fittings

 

[John Jackson]

No there are two

 

[Taylortwocities]

Ah, that may change things. Are those two lights controlled from the same switch?

Did you identify the two switch wires yet?

 

[John Jackson]

Yes one is a single switch and one is a double - the single switch control's the front light and the double controls the back and the front. I have identified the switch wire in both