4 gang light switch wiring

[EFLImpudence]

So, I see what I assume is the live feed in from the consumer unit (rightmost switch). But, the (black) switched live is using the same grey cable. How can this work - surely this is also from the consumer unit and not to a ceiling rose?

I only posted the diagram plus the link to the 'lighting and lamps' page in response to the above question from the OP.



The only thing that is clear in this thread is that the switch wiring is not 'usual' in that it has apparently been added to for additional lights.

There is one live feed which feeds all four switches.

Switches 1 to 4 Left to Right

1 Two-strapper system. The twin and earth cable goes to another switch.

2 One of the two single reds goes to the light it serves.

3 The other of the two single reds goes to the light it serves.

4 The only 'conventionally' wired switch with twin and earth containing the live and switched live from/to the light it serves.



That is all that can be determined from the pictures.
Presumably switch 4 cable goes to the rose of the light it serves, but may not, and the routes of the other wires can only, pointlessly, be guessed.

 

[geranium]

The red wire in that seems to be the switched live, now I'm just not sure what the black wire is given that the live is common and from the rightmost switch ...

To answer my own question, the black wire is a neutral wire connected some how to the two-way system.

There must be a junction box somewhere, because only the red wire (switched live) has continuity with the 4 gang, the black wire does not. I assumed it was the same grey cable, but it cannot be.

 

[EFLImpudence]

To answer my own question, the black wire is a neutral wire connected some how to the two-way system.

No, there are NO neutrals in the picture.
The blacks are switched live when the switch is on taking the supply back to the light.
Switch 4 is as in the previous diagram.

Switch 1 is like the first diagram here -

 

[AndyPRK]

EFLI has summed it up correctly. And actually there isn't a need for a junction box.

There is one live feed which feeds all four switches.

Switches 1 to 4 Left to Right

1 Two-strapper system. The twin and earth cable goes to another switch.

2 One of the two single reds goes to the light it serves.

3 The other of the two single reds goes to the light it serves.

4 The only 'conventionally' wired switch with twin and earth containing the live and switched live from/to the light it serves.

A picture of the roses would confirm.

 

[geranium]

To answer my own question, the black wire is a neutral wire connected some how to the two-way system.

No, there are NO neutrals in the picture.

Sorry, I don't think I explained what I was trying to say very well.

I agree that the first switch has two switched live wires (red and black). These are are from the same grey cable.

At the ceiling rose controlled by this switch, only the red wire has continuity back to the switch. The black wire from the same grey cable does not have continuity with the black wire in the switch, and is wired to the neutral terminal in the ceiling rose. (Hence the junction box comment, because the cable has seemingly been 'split'?)

As you rightly said before, the first switch is part of a two-way system. There are also two lights which are both affected by both switches - not sure if that makes a difference.

 

[EFLImpudence]

Sorry, I don't think I explained what I was trying to say very well.

I agree that the first switch has two switched live wires (red and black). These are are from the same grey cable.

At the ceiling rose controlled by this switch, only the red wire has continuity back to the switch.

Flip one of the switches - Power OFF.

The black wire from the same grey cable does not have continuity with the black wire in the switch,

Above.

and is wired to the neutral terminal in the ceiling rose.

Are you sure you have the correct wire or that it's not the switched live from the other two-way switch?

Wires can be anything WE want them to be.
They do not know what colour they are.

Please study the diagrams and lighting site so that you understand how it works.
Draw a diagram your self including the actual position of the fittings.
It will be easier to follow.

As you rightly said before, the first switch is part of a two-way system. There are also two lights which are both affected by both switches - not sure if that makes a difference.

No difference.

 

[EFLImpudence]

 

[EFLImpudence]

Four grey cables at one of the roses operated by two switches (leftmost switch)!

That will usually be -

Live 240V supply to the fitting. L, N, E.
Live 240V continuing from here to next room. L, N, E
To the switch. L to, SL back (in this case suspect JB somewhere because single at switch).
Switched live to the second light operated by switch SL, N, E.

 

[AndyPRK]

Assume your talking about the Left switch, 2 way here

I agree that the first switch has two switched live wires (red and black). These are are from the same grey cable.

At the ceiling rose controlled by this switch, only the red wire has continuity back to the switch. The black wire from the same grey cable does not have continuity with the black wire in the switch, and is wired to the neutral terminal in the ceiling rose. (Hence the junction box comment, because the cable has seemingly been 'split'?)

As you rightly said before, the first switch is part of a two-way system.

That twin cable from the left switch will goto the other switch which controls the light. and then a single to the rose.

You won't get continuity back to the rose at the same time.
You will find if you flip both switches, you now get contunity on the black wire but not the red.

 

[geranium]

Just a quick message to say thanks to everyone again for all the help.

I'll be sure to pay particularly close attention to the wiring of the ceiling roses when changing them!

 

[securespark]

Yah! Or ve vill get out ze vhips next time!