Wiring help for a double gang switch one room

[xbblade9]

Hi there, need help wiring this (image included) one part of the switch is suppose to light up 3 lights on side of the room and one the other side. But, I'm having trouble wiring it up with these cables pulled in and named like so.. Anyone any clues. Much appreciated. I included a link to an image.


https://ibb.co/NjCsJ1c

 

[telectrix]

a photo of the existing wiring would be better.

 

[xbblade9]

I have to figure it out before I go on Monday to do this. So ideally I want to have a plan in my head to where those 'switch/lines' labelled cables go where and the coms from one side of the room and the other coms where as well.

 

[littlespark]

Are those the cores of cables marked as switchline and com?
Why so many marked com?
Are some of them neutrals?
Wired in t&e?

 

[xbblade9]

Are those the cores of cables marked as switchline and com?
Why so many marked com?
Are some of them neutrals?
Wired in t&e?

Hi, the coms are the lights on one side and coms3 are the other side all t&e 1.5 and I guess switch/line is power because there used to be two switch that operated each room now it’s converted into one room.

 

[Dartlec]

Is each line in the diagram a core of the T&E or the whole T&E?

If it replaced an existing switch, then the most likely is that you have a permanent live in, then the switched line return to the light.

The original switch (depending on how old) probably didn't have a neutral at the switch, so if you are feeding those new lights from the switch directly with neutrals it won't work, you'll need to take the neutral from the original light (or whatever replaced it) to the new fittings.

Then you would have the incoming permanent live from each side into the COM on the corresponding switch terminal, and the other switched lives leaving into the L1 terminal. (Or possibly L2, depending on the switch and which one is used for 1 way switching - but not both)

If there are neutrals coming in and going out, then they should be connected together behind the switch in a suitable Wago connector or similar.

 

[telectrix]

if we are to believe the climate change prophets of doom, southampton will be under water in 10 years,so fit an IP68 switch.

 

[xbblade9]

Yes sorry the each line is a whole T&E, new cables were connected with the old through connector blocks I believe I can't rip the ceiling off as it has been already plastered. So I believe each COM is a fitting ? however from one side there are only 3 T&E sticking..

You think that from each side I am suppose to wire those 'switch/lines' into the each COM on the backplate ? and have to keep doing a trial & error on each COM T&E cable where they go in L1 ? or connect all neutrals together and all lives in a Wago connector?

It might seem so simple but who labelled all these twin and earths just made a complete headache as to do guess work. Sorry and thanks for your reply !

 

[westward10]

I see you are a trainee, who installed these cables and is this a private or work job.

 

[littlespark]

You can't just trial and error connect things up.

cables must come from somewhere else, another switch, or the light fittings... you need to find them and identify them properly.
Using a continuity tester, not mains voltage.

 

[Dartlec]

Yes sorry the each line is a whole T&E, new cables were connected with the old through connector blocks I believe I can't rip the ceiling off as it has been already plastered. So I believe each COM is a fitting ? however from one side there are only 3 T&E sticking..

You think that from each side I am suppose to wire those 'switch/lines' into the each COM on the backplate ? and have to keep doing a trial & error on each COM T&E cable where they go in L1 ? or connect all neutrals together and all lives in a Wago connector?

It might seem so simple but who labelled all these twin and earths just made a complete headache as to do guess work. Sorry and thanks for your reply !

If the 'switch/line' in the diagram is one Twin and Earth and is the original wire from the original fitting then it may well be line in (which would go to COM), and switched line out which would go into L1 with all the other lines for that 'side'.

Usually brown or Red will be permanent live and blue/black switched live (should be sheathed to indicate it's a switched live) but it's not guaranteed that it's that way round.

If it is like that, the issue may be whether you have a neutral at the switch at all and you'll have to test for that. (Hopefully any currently live wires are suitably terminated at the moment!)

If the new fittings are all being fed only from the switch then you'll need to have an incoming neutral from somewhere, which will go into a block with all the other neutrals.

You may need to check wiring at each fitting and connect the ends with a wago (all with no power of course!) and then check continuity at the switch to identify what each cable does. It's often quicker in the long run to do that, especially if the labelling hasn't been left clear for you.

I do hope it's a big backbox, that seems like a lot of cables for behind a 1 gang switch!

 

[xbblade9]

Photos if that helps:

https://ibb.co/FVdvp8T
https://ibb.co/4Yc9T8b
https://ibb.co/nPh0X9L

 

[westward10]

That is unbelievable. As already mentioned the only way to trace all that is with dead continuity tests.

 

[DPG]

Who installed the cables? Why aren't they finishing the job?

 

[FatAlan]

From the photo it looks like seven separate T&E cables in there? Looks like some of them are marked?

 

[westward10]

From his initial posts I think you have a supply in and six separate cables to each light, genius.

 

[FatAlan]

From his initial posts I think you have a supply in and six separate cables to each light, genius.

Wago the switch lines of each bank of lights together and connect to the switch. Line in to common with loop across to other common. Neutrals wago together and same with CPC. Just need to work out which light is which ?

 

[Dartlec]

That's a real mess to leave you to sort out. Hope you are already scheming your revenge!

Methodical and slow is the only way to approach it. Ensure the circuit is off and continuity test each cable to identify what it is, shorting the cables at each light fitting in turn.

Determine which does each light, and separate them/label them yourself. They will be the outgoing feeds that go to L1 (Line) and neutral connector(suitable connector with them all together in the back box)

Then work out what you have with what's left - hopefully an incoming permanent line and neutral.

The neutrals will all go together, and since this is the switch point, hopefully none of them are actually switched lines that aren't identified.

Is this a one way circuit? The way the wires are currently put into the switch suggests 2 way, but maybe that's just someone's attempt through trial and error?

If it's one way, you will only be using COM and L1 terminals, with nothing in L2