UK Lighting connections help please

[Gunny112]

I am somewhat confused as to why an upstairs landing light does not work unless the switch in the hall downstairs is switched to the off position. it defeats the object of turning it on downstairs and switching it off upstairs. I did not put this wiring in someone else replaced the switches and put them back in the incorrect order.
at the landing switch there are three cables one three core and two four core? at the switch the 3 and one of the four core cables neutrals are choc blocked together. all three Live cables were in L2 ?
What I did was to configure the wiring as per a two way switch but this left me with an extra yellow(sleeved) in the landing switch?? All lights work throughout the house apart from the landing light it can only be operated by turning the switch off in the hall only then does the landing light work correctly on and off. I don't understand why there is an extra four core cable at the landing light. Double switch in the hall for upstairs landing light and the hall light. single switch upstairs landing light.? your help is greatly appreciated not only to fix this problem but to educate my knowledge, thank you

 

[Marvo]

There's obviously an error in the wiring. Problem is with lighting arrangements there's invariable several ways the circuit could have been configured and wired to achieve the same end so the only sure way to sort it out is to start from scratch, test out all the wires, and reconnect accordingly. I'd suggest you just pay a sparky to come and do this for you, unless there's larger unknown problems it shouldn't take more than half an hour to sort it out.

 

[Gunny112]

There's obviously an error in the wiring. Problem is with lighting arrangements there's invariable several ways the circuit could have been configured and wired to achieve the same end so the only sure way to sort it out is to start from scratch, test out all the wires, and reconnect accordingly. I'd suggest you just pay a sparky to come and do this for you, unless there's larger unknown problems it shouldn't take more than half an hour to sort it out.

I think it’s looped at the switch instead of the ceiling rose and the two yellow wires are around the wrong way on the landing switch ??

 

[Risteard]

It's hard to tell as the picture isn't terribly clear, but do you just have a link between the backbox and the Class I switch with the cpc just terminated in a block connector and not actually earthing either the backbox or the switch?

 

[dmxtothemax]

could it have been a 2 way switch arrangemant ?

 

[Kidsolo]

This is a two way switch, right? everything else works except the two way switch?
I am not sure what you have on a UK switch, but wher i am from we have common, position 1 and position 2 and a loop.
the problem is in the upstairs switch. you have connected the downstairs position 2 (off position) to the upstairs common, instead of upstairs position 2. That is why you are only getting power to the upstairs switch when downstairs is switched off.
I hope i explained it right.

 

[dmxtothemax]

if it is a two way switch arrangemant ?
And if some one not knowing this has changed the switch
And not used the correct switch
This could explain the problems

 

[Lucien Nunes]

As per Marvo, the difficulty is working out what was intended, as there is more than one possible configuration. What I think I see is that the single switch has three cables with supply looped at the switch. The T+E and the right hand 3C+E are supply and loop, the yellow of that 3C+E being unused. The middle 3C+E seems to be used as 'conversion' 2-way with red=PL strapper, blue=SL strapper and yel=com.

At the 2-gang hallway switch, there are only two cables, so if both switches are used, the T+E must be a switch drop for the 'other' switch, not part of the 2-way. Therefore the light must be connected to the 2-way switch cables at a junction box and the 3C+E should simply terminate at the 2-way switch exactly as per the other end. The problem seems to be that the cables are muddled at this end, with some in the wrong switch.

Even if this inference is correct, and it might be a mile off, it is a non-standard configuration so I wouldn't recommend simply trying it without tracing. If the two lights controlled from this position are on different circuits, incorrect switch wiring may cause a dangerous interconnection between them. They appear to be interconnected now, so a hazard may already exist with one circuit being backfed from the other. The best way to eliminate that hazard is for an electrician to conduct a proper set of tests.

 

[Kidsolo]

as there is more than one possible configuration.

You are over thinking this. The rest of the house works, the problem is in the two way switches.
The bottom 2 way needs the "normally open" terminal swapped with the "common". that will get power to the top switch with both "on" or "off" selected. You might have to do the same with the top switch, depending on what the light is doing. Either way, the bottom switch is definitely swapped around.

 

[Lucien Nunes]

Can you explain, then, why it appears that in the 2-gang switch, the 3C+E seems to be split between two switches? Either the layout is completely non-standard and we can't guess at it, or the 1-way switch has accidentally got involved too.