3 Pole Switch Wiring Question

[Matthe1]

Trying to replace this existing 3 pole switch with a smart 3 pole switch, am I identifying these wires correctly? It appears there’s an expectation for fives wires including two traveller wires so is it likely the two blue are both travellers in which case am I missing a ground wire?

Help would be appreciated.

 

[littlespark]

Best wait for an American set of eyes, but at a guess from over the pond, the green will be ground, the two blues are both travellers, and the black is live (or switched live) There may not be a neutral there at all.
Is this a 2 way switch? As in one light controlled by two switches?

can you show the connections of your smart switch, or the wiring diagram supplied with it? You may have the type that doesn’t need a neutral to work

 

[Matthe1]

Yes, it’s one light controlled by two switches.

The smart switch does call for a neutral.

 

[telectrix]

doubt that the smart switch will work unless you can get a neutral to it. there are smart switches available that don't require a neutral.

 

[Matthe1]

This works with this set up so the one most likely is the neutral wire, however I’m still concerned that something isn’t correct as there’s only one traveller wire connected.

Is it possible there’s only a need for a single traveller wire or is it more likely it’s missing a ground wire?

 

[telectrix]

if you've got it working, it's most likely that you have it connected across hot and ground. that is verboten.

 

[Matthe1]

This is the concern. Ok, do what would be the correction needed for this? And why is it ‘working’?

Worth noting I did test the wires and only the bottom blue and black where ‘hot’ hence my assumption the top blue was the ground.

 

[westward10]

Highly unlikely the blue you have marked as ground is ground unless it has been repurposed (have you tagged them). Neutral is normally white or grey.

 

[Matthe1]

Highly unlikely the blue you have marked as ground is ground unless it has been repurposed (have you tagged them). Neutral is normally white or grey.

yes these were tagged by me

 

[westward10]

It is possible that is ground but it needs testing to be certain, same with the neutral. The most obvious colour for ground is the green but that may not be the case.

 

[telectrix]

This is the concern. Ok, do what would be the correction needed for this? And why is it ‘working’?

Worth noting I did test the wires and only the bottom blue and black where ‘hot’ hence my assumption the top blue was the ground.

you may find that the other blue becomes hot when the other switch is pressed, that will prove that it's a traveller.

 

[Matthe1]

That makes sense.

Ive noticed on the other switch there is a clear copper ground wire. Is it possible for the ground wire to be at only one end of the three pole?

 

[Matthe1]

That's reassuring teletrix.

I should clarify that the green wire was originally pigtailed and not connected to anything so I believe it's safe to assume this as neutral. My current assumption is the two blue wires are travellers (which I will test if the wire becomes hot after turning secondary switch on) and that this specific switch does not have a grounding wire but by having one on the other switch this should be okay.

Reasonable assumptions?

 

[westward10]

If your first switch is three way then the blues are travelers. Do not assume the green is neutral.