2 gang - 8 wires - 1 connecting red wire

[James_Raw]

I am replacing my hall & landing lights but made a school boy error.. I didn\\\'t record which wires went into which connection. 15 hours later I haven't worked out the correct combination. I have 3 cables:

1. -Red (Live)
-Black

2. -Red (Not live)
-Black
-Earth

3. -Red (Not live)
-Black
-Earth

Switch
top- L1 L2 Common

bottom- Common L1 L2

I also have 1 red wire that links two connections (again don\\\'t know which ones). I know the Earth wires go onto the metal case. can anyone help?!

 

[plugwash]

id get a sparky in it doesn't seem like any normal wiring practice and there may be other nasties like borrowed neutrals involved

 

[securespark]

Why do you make mention of the switch wiring? If you're just replacing the fittings, you don't need to touch the switches.

 

[ban-all-sheds]

id get a sparky in it doesn't seem like any normal wiring practice and there may be other nasties like borrowed neutrals involved

Sounds perfectly normal to me

1. -Red (Live)
-Black

2. -Red (Not live)
-Black
-Earth

3. -Red (Not live)
-Black
-Earth

1) will be the loop-in (I sincerely hope, BTW, that there is an earth conductor in this cable!)

2) and 3) will be the loop-out and switch cables, but without testing there's no way to tell which is which.

James_Raw - I hope you haven't made school-boy-error #2 in thinking that it's OK to work on your electrics without being in possession of a multimeter, as you now need to do a continuity test on the red/black conductors in each cable to identify which one goes to the switch....

 

[plugwash]

i thought he was refering to cables at the switch

my misreading

 

[securespark]

Actually, plug & Ban, I think he does mean the switch wiring - he mentions needing an earth for the box........

If it is switch wiring, then I'm a bit flummoxed, although the following strange method I came upon recently:

The cable with live wire fed as follows: red(live) to common of one switch, and black (switchwire of other light) to other common.

Then the two pairs left would be strappers but as for which is which, I don't know.

I'm NOT saying this is correct, but this is how I found a switch wired.

Need a Multimeter!!

 

[ban-all-sheds]

Actually, plug & Ban, I think he does mean the switch wiring - he mentions needing an earth for the box........

You could be right - I was concentrating on the fact that he opened with "I am replacing my hall & landing lights", not "I am replacing my hall & landing light switches"

If it is switch wiring, then I'm a bit flummoxed, although the following strange method I came upon recently:

The cable with live wire fed as follows: red(live) to common of one switch, and black (switchwire of other light) to other common.

Then the two pairs left would be strappers but as for which is which, I don't know.

I'm NOT saying this is correct, but this is how I found a switch wired.

Or he could be talking about the switch in the hall which has 1 gang used in a 2-way for the landing, and one gang as a 1-way for the hall. He's got one cable used as a single to provide a live feed, a short link to provide a second live feed, another cable used as a single for the switched live for the hall and a L1-L1/L2-L2 strapper going to the landing switch. In which case let's hope he has just the one lighting circuit, or he's likely to have a borrowed neutral.

Or we could stop all the guessing until he gets back with some clarification...

Need a Multimeter!!

Absolutely. I do hope you have one, James.....

 

[James_Raw]

Didn't realise I would get a response so quickly, thanks. To try and clear some questions up..
It is the light switch I am replacing, I have a two gang switch which when wired correctly will controll two lights (upstairs & downstairs), there is a second 2 gang switch upstairs that also controls the two lights.

I have applied securespark theory and have had some luck although if the upstairs light is switched on from the upstairs switch, I cannot turn it off from downatairs.

I do have a multimeter and taking all correct precautions.

 

[securespark]

I do have a multimeter and taking all correct precautions.

What? You're wearing a condom?

Glad you have had limited success with my theory. But you do need a MM to ascertain the ends of the strappers, which ones are live etc....

To find out which are strappers, join one end of a twin and earth together, and make sure all others are free and the power is off. Put a MM on the reds and blacks of cables at the other end with the thing set to Continuity.

You will get a beep when you connect the meter to the pair that are connected together at one end.

 

[ban-all-sheds]

To find out which are strappers, join one end of a twin and earth together, and make sure all others are free and the power is off.

Even better - make sure the power is off and then start joining ends together

 

[securespark]

Indeedy.