Confusing wiring

Hey folks!

Recently started with Hubitat and looking to get me a couple of light switches. I've confirmed my switches do have neutral wires, which are currently just connected together in the box so figure I can use switches with or without neutral (leave the neutral wires as-is for the latter).

Something did confuse me when I checked, namely that there are 3 pairs of cables going into my 1 way 1 gang socket, the live goes to the common port, the brown wires from the other 2 sets go to L1 and all three neutrals are connected together. It's a new house and this socket has never been changed since the house was built. I'm just surprised to have what looks like 2 sets of cables going off to the same one light fitting.

Of course if I get a switch for this I can wire it up the same, but I wanted to see what people's experience was and whether this was normal or an oddity?

How many lights does the switch turn on? Are the 2 L1's going to 2 separate lights?
I'm in the UK but have an older house with no neutral at the switches so I've not come across this setup before.

Is it possible one circuit is for a light and the other a fan?

Only one light fitting and no fan (it's a living room, not a bathroom) - I can't see where the wiring is going. I haven't opened up the ceiling rose to see what's going on in there.

I've been looking at various wiring diagrams with radial wiring etc, but those are all wired from the ceiling rose, not from the switch like mine.

I have a similar setup in a couple of boxes here, an extension from back in the 80's. I didn't look into changing them, as I didn't know. So replaced them with Xiaomi with no neutral switches. Had I of known, I'd have gone for the ones with neutral as they repeat :slight_smile:

Looking at the wiring, that's a 2 gang switch isn't it?

I didn't actually check whether it was 2 gang switch, but only one light fitting is attached and there are no other switches for that light. So from a functional perspective, it's 1 switch controlling 1 light fitting and that's it.

Out of interest (off topic) what do you mean they repeat? Is there a benefit to using a switch with a neutral wire here vs. using one without a neutral wire and just leaving these 3 neutral wires connected together in the back of the box?

And yeah, zooming in on the pic, it's a 2 gang switch, but only one side is connected (L1) with 2 brown wires in the same terminal.

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Yeah the Xiaomi switches with neutral are also Zigbee repeaters. So I'd go with neutral switches if you can, adds a bit of robustness to your Zigbee network :+1:

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I wonder... I wonder whether the electrician who wired this house was very forward thinking and prepped the wires to create a 2 gang switch with the dining room, allowing both fittings to be switched on/off with both switches at the same time?

Just for information, I had a Xiaomi light switch with neutral.
When I connected it to my hub my zigbee devices started playing up and dropping off.
Removed it and things went stable again.
For me these switches were a nightmare.
Just my experience, yours may be different.

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Oooow bummer!!!

I think it was a change in regs, I think all newbuilds have neutral, but not sure in which year that changed.

I was thinking maybe a ceiling fan fixture with lights as future expansion, not a bath fan.
Of course to check this you'll have to open the ceiling rose to verify.

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Ah gotcha, yeah could be there's wiring in there for some type of expansion. I was thinking along the same lines that it could be wired to the dining room next door in case we want to change it.

Anywho, I've not heard anyone going "no! don't do it! that's special wiring you must not touch!" :smiley: So I'll go ahead and get a switch, and just wire that in the exact same way as this one is, with a live, those two brown wires in L1 going to the fitting and the neutrals... maybe connected, maybe just as they are now (depending on switch).

As you have a neutral your choice of switches is greatly increased as non-neutral ones are very sparce.
As @Royski has said, neutral switches do usually repeat your zigbee devices helping you get a good zigbee mesh.
Make sure you get good repeaters though.
Enjoy your home automation journey. :+1:

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have you tested i would have thought the 2 are the live loop and the single is a switch live.

On A single switch it doesn't really matter which goes in which

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That's a good shout, could be...

have you a little light up screwdriver

No, I've got a multimeter knocking about somewhere in the garage, but screwed it all back together now. I've ordered a Wifi switch so will have a look when I change them over.

This is correct they just connected the loop in and out live to the wrong side of the switch but that doesn't make any difference. This is standard wiring now and is perfect for smart home. We do it like this as it's easier to test at the switch and makes it simple at the light. The only issue you have is that looks like a 25mm box .

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