Old light switches wiring

[MalcolmS]

Hi All,
I have these old light switches.
I understand this yellow / blue is the old pre 1980 colour scheme.
Is it correct that:
1. YELLOW with a red sleeve is LIVE
2. BLUE with a red sleeve is NEUTRAL
?
Thanks

 

[ipf]

No Neutral involved. Any cables with red sleeving should be switched lives, in this case 'strappers' for a 2way light.
Why do you ask? Are you changing the switches?
That back box lug on the 1 gang doesn't seem to be in the best of health.

 

[MalcolmS]

No Neutral involved. Any cables with red sleeving should be switched lives, in this case 'strappers' for a 2way light.
Why do you ask? Are you changing the switches?
That back box lug on the 1 gang doesn't seem to be in the best of health.

The electronic switch I am adding has "L In" and "L Out" and yes this switch does not require Neutral. "L Out" leads to the bulb.

Yeah the box lug looks loose, it's in a plasterboard wall with a void.

 

[littlespark]

First switch I presume is a 1 way and a 2 way…
Second switch is the paired 2 way.

Looking at the wiring, you may have a permanent live at both boxes, which could be 2 separate circuits.

Isolate before messing around.

Try to fix the screw lug, or replace the box entirely. Looks broken, not just loose.

If you have an electronic switch… which make? As they can work different ways.

Are you replacing both switches, or just one that controls both lights?

And finally… those are shallow boxes. Will you get an electronic switch to fit? You may need a plastic extension spacer to bring it out from the wall a bit.

 

[ipf]

The electronic switch I am adding has "L In" and "L Out" and yes this switch does not require Neutral. "L Out" leads to the bulb.

Yeah the box lug looks loose, it's in a plasterboard wall with a void.

Just get a pro in to sort it, Malcolm.

I see you're in London, though. A couple of hours' all in......£400ish???

Oh, Plus a tenner for mats.

 

[MalcolmS]

First switch I presume is a 1 way and a 2 way…
Second switch is the paired 2 way.

Looking at the wiring, you may have a permanent live at both boxes, which could be 2 separate circuits.

Isolate before messing around.

Try to fix the screw lug, or replace the box entirely. Looks broken, not just loose.

If you have an electronic switch… which make? As they can work different ways.

Are you replacing both switches, or just one that controls both lights?

And finally… those are shallow boxes. Will you get an electronic switch to fit? You may need a plastic extension spacer to bring it out from the wall a bit.

Yes, you are right, two separate circuits (upstairs, downstairs lights) but in 2-way configuration across 2 circuits.
Yes, I am going to fix the box lug
Yes, well spotted I will need the extension spacer for the shallow one.
Yes, same electronic switch per box
This is the diagram of the electronic switch.

 

[Avo Mk8]

Malcolm - I'm not sure what your question is!

Use the top left wiring diagram for putting one Sonos with the single switch, establish which of those two wires is permanent (L), wire then accordingly to the Sonos L terminals, and then wire the switch directly to S1 & S2.

Use the top right diagram to wire the 2-way switch, reconfiguring the 3 core cable to mimic that diagram. Put the other Sonos with this switch. Establish which of the two non-3 core conductors is permanent (L) as before, and wire that to the Sonos Lin as before, the other wire to Lout. Then wire the 3-core to match the circuit diagram for the S1 & S2 connections.

If you don't have test equipment, or are uncertain about implementing the diagrams, you may need some help.

 

[MalcolmS]

I have checked all the wires with a multimeter and the ones marked in violet colour are permanent lives. Permanent lives in each box are red and indistinguishable from the other red ones.

# 1-WAY SWITCH (upstairs)
COM - yellow (with red sleeve)
WAY L1 - blue (with red sleeve) + red -> permanent live
WAY L2 - 2x red

#2-WAT SWITCH (downstairs)
BOTTOM
COM - yellow (with red sleeve)
WAY L1 - red -> permanent live

TOP
WAY L1 - blue (with red sleeve)
WAY L2 - red
COM - red

From what I red online COM supposed to be LIVE (PERMANENT) and L1 should be SWITCHED LIVE but in this case permanent goes to L1 in both boxes.
Does it makes sense to you or is it mixed up?

 

[ipf]

We can see what is going on from your photos. You obviously don't understand the 2-way wiring method involved.
Don't take as red all you reed online.
As above (and previously) professional help is advised.

 

[Avo Mk8]

You misunderstand the terminals of the switches, or if you don't, you chose a bizarre way of representing the information in your table of results. Each switch has terminals in a triangle, as I've tried to show in the second pic below.

So unravelling your list, you have traditionally wired circuits, nothing is mixed up.
It's like this for the two-way circuit:



It needs to be wired as I suggested previously.
In order to implement the 2-way Sonos circuit, the upstairs wiring to the switch will have to be changed.
If you are not sure how to do this, do get some help, as there is plenty of opportunity to blow up the Sonos device, have an accident, or leave something dangerous behind.

 

[davesparks]

From what I red online COM supposed to be LIVE (PERMANENT) and L1 should be SWITCHED LIVE but in this case permanent goes to L1 in both boxes.

From what I've read online the earth is flat and run by giant lizard people who live underground.

Don't believe what you read online.

There is no 'supposed to be' as far as the terminals on those switches are concerned. Com, L1 and L2 are just three terminals on a switch which will be connected differently depending on how they are being used, for extra fun different manufacturers sometimes label them differently.

Does it makes sense to you or is it mixed up?

Makes perfect sense to me.

 

[MalcolmS]

Hi again Everyone,
You were helpful to me especially Avo Mk8 is very understanding. I made this diagram.
Perhaps you will say it's wrong

So far I connected the switch downstairs, it works, I left the blue and yellow wires aside for now but for some reason I lost the current upstairs, not sure why. It's on a separate circuit, the RCB is ON but no lights upstairs.

 

[Avo Mk8]

So far I connected the switch downstairs, it works, I left the blue and yellow wires aside for now but for some reason I lost the current upstairs, not sure why. It's on a separate circuit, the RCB is ON but no lights upstairs.

Your diagram is of how the old switches are/were wired, and as far as I can see, is correct.
It does not represent how to connect the Sonos.

With the yellow and blue wires disconnected, the light will never come on because you have removed the way the bulb gets power.

The Sonos needs to be connected as per the top right diagram in your post #6.

This forum is not supposed to give step by step instructions for obvious reasons.
I'm feeling that since you are already involved in this, somewhat against the advice already given, I will give a factual explanation of the necessary wiring. It needs to be carried out safely and competently, which you need to organise.

The red wire to the upstairs light bulb should be in Sonos L out, and the incoming power (circuit 2) red wire should be in Sonos L in.

The end of the yellow wire that used to be in upstairs switch com (that you say is presently unconnected) should be in Sonos S2.

The blue wire (that you say is presently unconnected) should go to the upstairs switch L1 where it was originally.

A short piece of insulated wire is needed between the upstairs switch Com and Sonos S1.

The end result should be that there is only one wire in each old 2-way switch terminal, and only one wire in each Sonos terminal.

 

[MalcolmS]

Ok, thanks again.
I meant the lights not only in the hallway but across the whole 1st floor are gone.
RCB says "lights+smoke detector". When that RCB is on I can see the green light on the smoke detector but other than that no power to any of the lights. When off the green light on the detector goes off as well. The red wire in upstairs light socket that use to have current is dead now. Did I blow some fuse or the RCB malfunctions?

 

[Avo Mk8]

Ok, thanks again.
I meant the lights not only in the hallway but across the whole 1st floor are gone.
RCB says "lights+smoke detector". When that RCB is on I can see the green light on the smoke detector but other than that no power to any of the lights. When off the green light on the detector goes off as well. The red wire in upstairs light socket that use to have current is dead now. Did I blow some fuse or the RCB malfunctions?

Oh, I see, I hadn't understood that, sorry.
Difficult to diagnose remotely.
Is the individual Breaker that tripped, an MCB, RCBO or an RCD. Unusual to be the latter for an individual circuit?
If switching the 'RCB' causes the smoke detector light to be on/off, sounds as if the breaker is providing power when on.
Is there some other protective device on your lighting circuit? Nothing else tripped?

Have you put the wires back in the upstairs switch exactly as they used to be, and if so does that restore power? There might be a link to those cables somewhere we don't know about?

 

[MalcolmS]

Oh, I see, I hadn't understood that, sorry.
Difficult to diagnose remotely.
Is the individual Breaker that tripped, an MCB, RCBO or an RCD. Unusual to be the latter for an individual circuit?
If switching the 'RCB' causes the smoke detector light to be on/off, sounds as if the breaker is providing power when on.
Is there some other protective device on your lighting circuit? Nothing else tripped?

Have you put the wires back in the upstairs switch exactly as they used to be, and if so does that restore power? There might be a link to those cables somewhere we don't know about?

As far as I can see nothing has tripped in the consumer unit. There is a separate fused switch next to the consumer unit (it says smoke detector) I reckon it's the downstairs one? This rather old consumer unit is going to be replaced at some point this year.

Do you mean I broke the series? I am going to check all the wires for current.

 

[MalcolmS]

I checked all the exposed wires upstairs and none of them are live.

I admit at the time I was messing around with a ceiling rose in the bathroom but this one is only 3 wire (green-yellow one grounding the ceiling rose and two red ones that are not live)

The fused switch next to the consumer unit is for both smoke detectors upstairs and downstairs one, so when this one is OFF both smoke detectors go OFF.

 

[Avo Mk8]

Is the MCB on the very right labelled "Lights & smoke alarms" the one you turned off when you said turning it off made the green light on the alarm go off?
Have you turned that MCB off and on again since the fault. Very rarely a MCB can trip without its lever going down. Just checking!
I'm afraid I have no idea why power should no longer be present for upstairs lights, unless you have disturbed something, possibly unknowingly, somewhere!

 

[Avo Mk8]

I admit at the time I was messing around with a ceiling rose in the bathroom but this one is only 3 wire (green-yellow one grounding the ceiling rose and two red ones that are not live)

It's unusual not to have a black neutral wire at a ceiling rose, or rather, unusual to have the neutral as red. Are you sure there aren't any other wires that might have escaped from that ceiling rose?

 

[MalcolmS]

Is the MCB on the very right labelled "Lights & smoke alarms" the one you turned off when you said turning it off made the green light on the alarm go off?
Have you turned that MCB off and on again since the fault. Very rarely a MCB can trip without its lever going down. Just checking!
I'm afraid I have no idea why power should no longer be present for upstairs lights, unless you have disturbed something, possibly unknowingly, somewhere!

Correct, it's that MCB that disconnects power to upstairs lights and that smoke detector upstairs.
The fused switch (not on the pictures) but next to consumer unit when OFF switches both upstairs and downstairs smoke detectors OFF.
I did switch this MCB several times and to OFF position not to work on live wires.

 

[MalcolmS]

It's unusual not to have a black neutral wire at a ceiling rose, or rather, unusual to have the neutral as red. Are you sure there aren't any other wires that might have escaped from that ceiling rose?

I said it wrong. It's not a ceiling rose in the bathroom but just a pull cord switch but I was wondering if there is anything in one of those ceiling roses that can trip. I haven't been touching them. I reckon to access roses I need to go to the loft.

 

[nicebutdim]

I said it wrong. It's not a ceiling rose in the bathroom but just a pull cord switch but I was wondering if there is anything in one of those ceiling roses that can trip. I haven't been touching them. I reckon to access roses I need to go to the loft.

If the tripping is a new development, it's more than likely going to be related to recent tinkering.

 

[ipf]

I checked all the exposed wires upstairs and none of them are live.

I admit at the time I was messing around with a ceiling rose in the bathroom but this one is only 3 wire (green-yellow one grounding the ceiling rose and two red ones that are not live)

Sorry to say it but this sums things up nicely.

 

[MalcolmS]

If the tripping is a new development, it's more than likely going to be related to recent tinkering.

I know tripping would relate to that but MCB hasn't tripped once while I was doing my thing.

 

[MalcolmS]

Sorry to say it but this sums things up nicely.

I just unscrewed the pull cord switch to find out which of the two red wires is live.

 

[nicebutdim]

I know tripping would relate to that but MCB hasn't tripped once while I was doing my thing.

This was a switch change which started on May 27th and has progressed to a number of other problems during the course of almost two weeks. Forum rules prohibit step by step instructions and this thread is a prime example of why. Looking in previously untouched places isn't likely to yield a solution, but may well compound current issues.

 

[MalcolmS]

This was a switch change which started on May 27th and has progressed to a number of other problems during the course of almost two weeks. Forum rules prohibit step by step instructions and this thread is a prime example of why. Looking in previously untouched places isn't likely to yield a solution, but may well compound current issues.

I understand however the number of problems is only 2:
1. understanding 2-ways switch
(I don't need step by step instructions since I worked it out with the help of Avo Mk8 and probably I don't need this to work 2-way since I can control it electronically).

2. loss of power on upstairs lights

I agree re compounding the current issue by looking into untouched places.

Since any of the existing exposed wires is live even if put everything back together as it was originally (like on the pictures) I don't think this will just come back up. MCB haven't tripped so it must be something else or it's faulty. I cannot understand the loss of current on the use to live wire.

I understand you assume I am a noob who just messed something else up and didn't tell you but I didn't touch anything else apart from that pull cord switch which I don't need an electrician to replace it. I have done that at least 5 times in the past.

 

[nicebutdim]

I understand you assume I am a noob who just messed something else up and didn't tell you but I didn't touch anything else apart from that pull cord switch which I don't need an electrician to replace it. I have done that at least 5 times in the past.

My comments are not about whether or not you're a 'noob', but whether or not it is advisable for people to provide further instruction.

There are electricians out there who struggle with certain types of lighting circuit, but the key is developing an understanding of how a circuit is wired and not randomly guessing which accessory to look inside next.

The likelihood of a random fault developing here is infintesimally low and the likelihood of something not having being put back as it was is exceptionally high. Somewhere a conductor hasn't been secured back into its terminal, has been placed in the wrong terminal or has broken after being disturbed.

These are simply my thoughts and others may disagree.

 

[westward10]

Return the wiring to the switches as it was before and if it still doesn't function then get an electrician involved. @Avo Mk8 has been incredibly helpful but from a distance we cannot suggest what is happening.

 

[MalcolmS]

Thanks everyone