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

 

[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