Switch wiring

[Nasko31]

Hi guys,

i’ve got a triple switch downstairs that controls a ceiling light, an outdoor light and a ceiling light upstairs.
I’ve got a single switch that controls the light upstairs as well however i can only switch the light on/off from whichever switch i’ve used to turn it on.
Can you please help?

 

[Lucien Nunes]

Did it ever work correctly? If so, did anything change or was any work done that caused the problem? Superficially the wiring looks OK, although we can't see which cables each of the wires in the triple switch comes from.

Note that the three downstairs switches seem to share a single permanent feed, and the strappers are what looks like twin-red & earth with one red core from the upstairs switch going to the light, so there is a significant chance you have a 'borrowed neutral' configuration. This doesn't affect how the switching works, but it does mean there is a risk of shock when working on the wiring unless both upstairs and downstairs circuits are isolated.

 

[radiohead]

I'd also be concerned about lack of earthing to the metal faceplates.

 

[Nasko31]

Did it ever work correctly? If so, did anything change or was any work done that caused the problem? Superficially the wiring looks OK, although we can't see which cables each of the wires in the triple switch comes from.

Note that the three downstairs switches seem to share a single permanent feed, and the strappers are what looks like twin-red & earth with one red core from the upstairs switch going to the light, so there is a significant chance you have a 'borrowed neutral' configuration. This doesn't affect how the switching works, but it does mean there is a risk of shock when working on the wiring unless both upstairs and downstairs circuits are isolated.

It’s been like that since i moved in. I just assumed it wasn’t wired correctly.
The switch controlling the upstairs light (from the tripe switch downstairs ) is on the left on the picture.
And ok point taken. I’ve isolated the both while checking them anyway.
Any idea how to fix it?

 

[SparkyChick]

I would say the wiring is wrong because the 3G switch appears to have inverted terminal sets....

L1 L2 COM L1 L2
COM L1 L2 COM

But appears to be wired as though the switches are all laid out in the same direction.

 

[westward10]

I would say the wiring is wrong because the 3G switch appears to have inverted terminal sets....

L1 L2 COM L1 L2
COM L1 L2 COM

But appears to be wired as though the switches are all laid out in the same direction.

I think you are spot on there you can just make out some of the markings.

 

[Lucien Nunes]

Not sure that what we can see indicates the wiring is wrong, although I agree it is quite likely to be wrong if it has never worked. I made it that that outer two switches have PL on 1-way and SL on Com, and the middle switch has PL on Com and the strappers on 1-way and 2-way, which is OK if the cables are what they seem to be and the middle switch is supposed to be the 2-way. It would help to see the individual cores emerging from the cable sheaths.

If, as it appears, it is a 'conventional' 2-way with PL on downstairs Com, two strappers and SL on upstairs Com, and the wiring is intact and correct, then the only logical mode of failure that would create the specific behaviour that the OP describes, is that one of the 2-way switches (it's impossible to tell which) has either L1 or L2 shorted to Com. This effectively reduces it to two 1-way switches in parallel. If it's the downstairs switch that is shorted, then in one position both strappers are live so the upstairs switch can't turn the light off, or when the top switch is towards the strapper that's always live then the downstairs switch can't turn it off. Similar logic applies if it's the upstairs switch that's faulty, or if one strapper is shorted to PL or SL elsewhere. Permanent shorts in light switches that do not manifest in jammed or faulty mechanical action are rare though, so I think it's equally likely that it has never worked because the wiring is wrong.

 

[westward10]

As per #5 from what I can make out with a bit of assumption it is currently connected like this or similar. @Nasko31 which switch on the three gang switch also does the landing to confirm or correct my drawing.

 

[Lucien Nunes]

That's definitely one of the options, OP let's see where those reds go! Although, I would imagine the OP would have drawn attention to the fact that (with one position of the upstairs switch) the middle switch weirdly changed over between hall and upstairs.

 

[Nasko31]

FYI - All fixed now ? thanks for your support.

 

[westward10]

Were we correct about the switch connections.

 

[Nasko31]

Were we correct about the switch connections.

Your assumptions were correct yes.
The left switch on your drawing controls the landing as well.

 

[westward10]

Glad you sorted it.