Can anyone help me understand this light switch wiring?

Joined
16 Jun 2016
Messages
64
Reaction score
3
Country
United Kingdom
Hi All

Hoping someone can help. We have a 3 gang switch in our utility room, and after 3 years I still don't know what 2 of the switches do.

I had assumed they were dead/old lights, however I have just taken the switch off as I am looking to add an additional light to the room, and found some wiring that I just don't understand!

Can anybody shed any light on the situation?? (sorry, rubbish pun).

Hopefully there is a diagram of the wiring attached - and it makes sense.

Thanks in advance.
 

Attachments

  • 20190131_190244.jpg
    20190131_190244.jpg
    153.6 KB · Views: 406
Sponsored Links
Switch 2 obviously doesn't do anything and is just acting as a connector.
Switches 1 and 3 look like they operate a light although, as you say, one of them doesn't. Which one doesn't?

I could guess at what all the wires are but I don't think it would be wise because there are a couple of things that don't look right.
Are you certain that you have drawn everything correctly?

What do the arrows signify?
 
Hi EFL

Thanks for the reply.

Switch 1 is a complete mystery. The best possibility is that it was a switch for an old outside light which is mounted in the soffit and long dead. Don't have a ladder big enough to check - but its on my to do list.

Never seen a switch used as a connector! New one on me!

Switch 3 is the ceiling light in the room, which works correctly, but as far as I can see, is not wired like a traditional 1 way switch.

I have double checked the drawing and its correct - however i missed that the yellow on wire 3 has red sleeving.

Any idea why there are 4 wires into 1 3-gang switch - and why one of the switches would be used as a connector?

My thoughts so far are:

Wire 1: Switch wire for an unknown light
Wire 2/3: Not sure, my bets guess is that they are the lighting ring, however if thats anywhere near true I would love someone to explain it to me!
Wire 4: Switch wire for the ceiling light.

Cheers
 
Switch 1 is a complete mystery. The best possibility is that it was a switch for an old outside light which is mounted in the soffit and long dead. Don't have a ladder big enough to check - but its on my to do list.
Ok.

Never seen a switch used as a connector! New one on me!
Nothing unusual. It's just that there is no output from the switch.

Switch 3 is the ceiling light in the room, which works correctly, but as far as I can see, is not wired like a traditional 1 way switch.
Well, it is. The supply is linked from one of the other switches, but we can't tell which.

I have double checked the drawing and its correct - however i missed that the yellow on wire 3 has red sleeving.
Ok.

Any idea why there are 4 wires into 1 3-gang switch - and why one of the switches would be used as a connector?
It's nothing unusual but I can't make sense of yours - and as above.

My thoughts so far are:
Wire 1: Switch wire for an unknown light
Wire 2/3: Not sure, my bets guess is that they are the lighting ring, however if thats anywhere near true I would love someone to explain it to me!
Wire 4: Switch wire for the ceiling light.
Ok.

I would advise you - or an electrician - to disconnect all the wires and start again.
There are too many things that don't make sense.
It looks as if the switches used to do something else and someone has fiddled with it on one or more occasion and altered the use without sufficient knowledge.

This is how it might work from what you say, but I have no idea what the two extra wires still connected to the switches do.

upload_2019-2-1_13-12-26.png
 
Sponsored Links
What are the blocks in the middle of the sketch?

Looks like a three plate rose?

Think EFL is right. When you look at which cable they come from, the individual wires look like they're in the wrong terminals.
 
The blocks are chock bloc. All of these wires are wedged in the back of a single 3 gang switch.

I am 100% in agreement that someone has been fiddling - would fall in line with a number of other things in this house (14 different cold water pipes in various parts of the bathroom or 11 different telephone points including 1 in the bathroom?!?)

Taking it all apart and starting again does seem like a sensible next step
 
Lights are NOT wired in rings.

Hi Winston

You are of course 100% correct, a mis use of terminology on my part.

At no point did I mean to imply it was actually in a ring....although given the confusing nature of the wiring you never know!

The mis use of terminology aside, do you have any experience with wiring such as this?

Thanks in advance.
 
Hi All

I have spent some time today investigating this wiring, and have some additional information....

Switch 1: Is 100% a disused outside light. I have disconnected it at both ends and made safe. Problem solved.

Now onto the strange wiring:

Wire 1: Was deffo the switch wire for the outside light
Wire 2: If I take the red out, none of my downstairs lights work, apart from the 2 way switch for the landing light. All of the upstairs lights work as normal. Can anyone shed any idea why someone may do this?
Wire 3: Same deal as wire 2, If i disconnect the red, my downstairs lights don't work, only upstairs. The yellow with red sleeve is permanently live, but doesn't seem to do anything if removed. Not sure what this is all about.

Basically, if i don't have the red from wire 2 and the red from wire 3 connected, I don't have any downstairs lighting.

So, my gut is that this is a huge mess and I am best tidying up the best I can and leaving well alone. However, I would be really happy to receive any further input.

Many thanks

DallyPro
 
Switch 1: Is 100% a disused outside light. I have disconnected it at both ends and made safe. Problem solved.
Ok

Now onto the strange wiring:
Wire 1: Was deffo the switch wire for the outside light
Ok.

Wire 2: If I take the red out, none of my downstairs lights work, apart from the 2 way switch for the landing light. All of the upstairs lights work as normal. Can anyone shed any idea why someone may do this?
Wire 3: Same deal as wire 2, If i disconnect the red, my downstairs lights don't work, only upstairs. The yellow with red sleeve is permanently live, but doesn't seem to do anything if removed. Not sure what this is all about.
That might not be anything unusual apart from the yellow which is obviously still connected somewhere.
Lighting circuits are just in line with branches.

Basically, if i don't have the red from wire 2 and the red from wire 3 connected, I don't have any downstairs lighting.
That's ok.

So, you could do this - which would look more usual.

upload_2019-2-16_15-6-11.png


I am puzzled why wire 2 Blue does not go into the Neutral block but you had better leave it where it is for the time being.
 

Attachments

  • upload_2019-2-16_15-4-31.png
    upload_2019-2-16_15-4-31.png
    511 KB · Views: 235
Wire 2: If I take the red out, none of my downstairs lights work, apart from the 2 way switch for the landing light. All of the upstairs lights work as normal. Can anyone shed any idea why someone may do this?
Wire 3: Same deal as wire 2, If i disconnect the red, my downstairs lights don't work, only upstairs.
On second thoughts that doesn't really make sense.
 
I would have thought that if wire 2 was a live feed, the blue would go to the neutral block, but it doesn't.
D'oh Edit: EFL has just said that....
 
On second thoughts that doesn't really make sense.

I would have thought that if wire 2 was a live feed, the blue would go to the neutral block, but it doesn't.
D'oh Edit: EFL has just said that....

That was my thoughts....it makes no sense at all. The downstairs lights will only work if the red cables from wire 2 and 3 are connected, and yet the neutral from wire 2 seems to be completely irrelevant.


EFL: Thanks for taking the time with paintbrush! Really appreciated. That makes perfect sense to me, and will at least tidy things up a bit.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top