How do I fit a two-way switch?
Two-way wiring can look very complicated at first, however, as long as your lighting is working well on your manual switches, it should be simple to swap to Lightwave’s Smart series.
If you’re not comfortable doing this yourself then please consult a qualified electrician.
Before you start
Shut off the power to the lighting circuit. Unscrew the faceplate of the switch to remove it from the back box. Take photos of the existing wiring at the back of each switch as it can be very useful to refer to at a later stage. Try to capture which terminal goes with each wire.
Two-wire or three-wire system
It is important to understand what system you are working with and it’s not as difficult as it may sound. Look at the back of each switch: you should see wiring terminals labelled ‘L1, L2, and C’. If both switches have no more than one wire fitted in to each terminal then you have a three-wire system. If one of the switches has more than one wire in both the L1 and L2 terminals then you have a two-wire system. Once you have identified your system, please follow the steps in the section below that applies to your set up.
Two-wire system
For both switches, move all wires fitted to the L1 to the L terminal on the Lightwave switch. Move all wires fitted to the L2 to the X terminal on the Lightwave switch. Wires in the C terminal are not required and can be safely terminated or removed altogether.
Three-wire system
At the first switch, move all wires fitted to L1 to the L terminal on the Lightwave switch. Move all wires fitted to L2 to the X terminal on the Lightwave switch. Move all wires fitted to C to the L terminal on the Lightwave switch.
At the second switch move all wires fitted to L1 to the L terminal on the Lightwave switch. Move all wires fitted to L2 to the X terminal on the Lightwave switch. Move all wires fitted to C to the X terminal on the Lightwave switch.
What if I have more than two switches in the circuit?
This is typically known as intermediate switching. It’s largely the same as two-way switching, but there is a specialised switch in the middle and additional wiring. You can spot this switch by looking at the back of it - it will have two sets of L1 and L2 terminals.
To add a Lightwave dimmer to this set up, you still need to follow all the steps above, but when you come to this particular switch, you need to move one set of L1 and L2 wires to the L terminal on the Lightwave switch and then move the other L1 and L2 wires to the X terminal on the Lightwave switch.
Finally, you need to create an ‘automation’ in the app to group these devices together so when one Lightwave dimmer is switched the other will too. To do this, you will need to open the app (let’s assume you have already registered your Link Plus and added your devices), click the ‘+’ symbol, select ‘Automation’, and choose ‘Two-Way Switching’. From here the app will take you through the set up steps. Please note that multi-way switching will not work until automations are created in the app.
For all installations, only the primary channel requires a L (live) wire, as the live in the primary side powers the whole module. The S (signal) terminal is non-functional on the Smart Series dimmers for multiway switching, as the pairing of these is done using the Lightwave Link Plus app, so if you have one of these S terminals, please ignore it.
Comments
16 comments
It's now 8th January and you promised instructions "during December 2017" (see above). Please can you update this.
This needs a bit more information.
I have the first switch in without a problem, but the wiring of the 2nd switch is confusing. I can't seem to get it working without one of the switches losing power.
Figured it out.
Wire the first switch in the series as normal.
The 2nd switch, wire the first half as normal.
The trick comes with wiring the 2nd half which feeds off the primary switch. Leave the live empty and put the 2 wires into the neutral slot.
I can’t seem to get my gen 2 light switches to work on an existing two way circuit, one switch will work however the second switch has no power feed, can anyone help? Three wires in each back box instructions say live in and live out what happens to the third wire?
please help as I’m trying to do this for my son who is rapidly going blind
I am also confused. Can you provide typical wiring diagrams.
I also have a 2 gang downstairs and a 1 gang upstairs so I am worried it will link the separate upstairs and downstairs circuits through the 2 gang dimmer.
Please help us out here.
I’m having the same issues. I replaced two existing switches using the same wiring but it didn’t work.
That wiring diagram is definitely half complete... I assumed button 2 would be the same (repeat) wiring layout.
I did it, and it doesn't work. Constantly both circuits are "on" and the buttons are constantly flashing green, pushing both buttons (on/off) won't start the linking... So I'm going to have to return the product...
And "yes", it linked upstairs and downstairs lighting circuits...
Closer reading that the whole unit is powered by 1 live wire... this would mean that existing live wire for lamp 2 is not required?
I would give that a go, however, for my setup
button 1 = "live" in upstairs wire circuit & neutral upstairs wire circuit
button 2 = "live" in upstairs wire circuit & neutral downstairs wire circuit
I'm no sparky but wouldn't that cause some sort of problem? maybe trip a RCD or something?
I have this product on a normal 2 gang is okay, but 2 gang + 2-way doesn't work for me
So... Each smart series 2-gang switch requires only one live in. Ok. But my bottom of the stairs switch gets live in from the downstairs lighting circuit and my tops of the stairs switch gets live in from the upstairs lighting circuit. Now as per the Lightwave wiring diagrams for 2-way switching; switched live-out (X) should be connected between the two switches. Great. Now when I turn on both dimmers I’ll bridge the downstairs and upstairs circuits, overloading the lights... Errrr... That’s not good! Where’s the wiring diagram for how to do this properly?
That was my exact problem, it would bridge the two circuits.
Have you tried to connect the light to the upstairs dimmer and then just link the downstairs one virtually in the app?
Nah, LW development as not getting anywhere so I binned LW and changed all to Hue.
- drawback was no power switchs on Hue (but I'm seeing some now)... pluses, OMG the things you can do with the lights... especially the colours - syncing with a movie, wow.
@Adrian Rockall - I would do that, but unfortunately the left-most gang as you look at the back of a switch (primary channel) requires a complete circuit otherwise the module won’t power on & for my downstairs switch that is the gang that needs to control my upstairs light... Snookered.
@Tak Chiu - I had Hue but decided to change to SmartSwitches. Hue needs the switch left on and the kids / guests of course turn lights off/on at the switch!
The solution I found for the hue switch was a cover plate that goes over the normal switch and a hue dimmer fits on top. I use that in a bedroom that has a ceiling fan which only has one connection for the fan and the light.
I have the covers aswell - I swapped out the LW switches with some basic MK ones and the cover goes on top with a Hue remote magnetically on top - so you can leave the remote on it or take off
I also have 2 different wireless batteryless (kinetic?) switches which I can put anywhere
- I have the official round one which is nice for 1 touch mood changes
- and a "niko" branded square one with 4 buttons with short/long hold assignable to anything from the app - individual lights or moods or rooms or upstairs or downstairs...
- the "niko" in theory can replace the official light switch, but I don't like hard wiring it "on", hence I'm keeping the switches covered (unless a 3rd party comes up with ta product that has both the mechanical switch + wireless kinetic)
So the stairs have their mechanical switches but covered so guests can't change the "always on" switch underneath - and up/downstairs can be controlled from the remotes or wireless switches.
When my wife had mobility problems in the house, I added the infrared sensors and all the hallway lights were activated by them - didn't use the switches at all.
I had the LW infrared device for downstairs, but found I had to change the battery quite often, and the timing settings were switches on the device itself - while the Hue is all on the app, including sensitivity and testing of sensitivity :)
Ok, so after talking to Lightwave support there was a simple solution; they sent me an older mark I (you can only buy mark 2) dimmer, where the right-most gang (as you look at the back of the switch) is the primary channel... Problem sorted. Simples! After spending a lot of time with these switches the most important lesson I learned was never use the existing wiring between switches. (Some wiring diagrams on these FAQs are incredibly confusing). Just wire in the main switch to your light - additional switches just need power. Use automation in the app to have them all operate the light.
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