Hi,
I can’t seem to find a 3 gang smart switch that works with only switch live, which I understand is the standard here. I can’t use neutral or a single main live wire.
When I’ve looked for no neutral smart switches (or relays), they still seem to need a single mains live wire rather than one for each switch.
I purchased one 3 gang smart switch but it needed 1 mains live, with 3 smart live out ie. 4 total wires. My builder said that won’t work as the 3 gang installed has 3 live in and 3 switch live out = 6 wires. there is no mains live nearby to utilise.
If you have an amazon or other UK link that I could utilise for 3 gang smart switches (wifi or zigbee) that would be really helpful.
Is this a common problem in UK smart home attempts, or am I completely misunderstanding how to wire these up?
all 3 lights in a new kitchen extension. I’ve attached the pics of the 3 gang switch wiring, although a bit unclear to see.
I’ve also attached the 3 gang smart switch which I had purchased. builder said it wouldn’t work with the kitchen wiring. He used it in the porch instead as wiring wasn’t setup there, so put a mains live into the switch and 3 switch live out. He didn’t use the capacitor as in diagram but it seems to work perfectly in porch.
First, install devices behind the ceiling rose or in a fitting. All connections are there, not at the switch in the UK.
All conductors need two layers of insulation for UK BS7671, so an outer plastic box may be required (and yes, this is possible). A hole saw to cut through the ceiling between the rose screws works if there is no access from a loft.
No neutral looks attractive, until you try it and find random flashing, LED bulb constant glow, poor dimming - bulbs are no longer a simple resistive load able to trickle a little current for the controller when off.
Second, please try the forum search. I’ve answered very similar questions several times - the truth is out there…
This is why you speak to an electrician for this kind of stuff. Apparently your builder has never heard of china connectors or Wagos or all the ways 3 cables can be bound together with an “extra” short piece of cable, which is used to connect to the Live on the switch.
The only way what you currently have will not work is if you have a 2-way switch, where any of those 3 lights can be controlled via multiple switches in different locations.
Call an electrician, and if you want to avoid flickering lights, follow @FloatingBoater’s advice or ask the electrician to pull a neutral from the closest light source.
Pro tip - swap SPCO 2-way switches with MK Grid retractive “push on” switches in parallel.
That way the triple plus CPC for 2way can become phase, neutral, switch and CPC - effectively you gain a spare conductor.
Push any parallelled switch, the module sees switch input, and the load toggles. If you use dimming modules, any push switch can set the dim level.
This doesn’t get neutral to one 2-way switch plate, but 75% of sparky tasks are getting wires from A to B through walls. Good sparkys run cables so you can still use the wall afterwards!
Also consider multiple gang switches often get less use after automation - you set scenes or use motion sensors, only leaving physical switches for backup and visitors.
Get an electrician in. If the three lights in your kitchen are all on the same circuit, then they all share a permanent live. You could share this from one of the pendants and then one of the now redundant additional permanent lives in a different way. You would feed switches with a single live and swap the lives and switched lives round in the other switches, as such, the sleeved blue cores could be used as a neutral (remove sleeving) by changing them at the pendant, without impacting on the switching of any of the lights. This is only an option if 2 or more of the lights are on the same RCBO or MCB in the consumer unit. An electrician can advise.
I’ve got a similar switch and should work just fine with yours. The capacitor just taps in to the neutral of the L1 (could be light/fan) for the switch to boot up.
