Installing a Smart 2-Way 2-Gang Switch

[Jetheat]

I have a set of lights upstairs and a set of lights downstairs.
There is a 2-gang switch at the bottom and a 2-gang switch upstairs.
So both switch locations allow me to control both upstairs and downstairs with the 2-way 2-gang setup.

Both upstairs and downstairs are on different circuits.

The switches are all dimmers, although my 3 bulbs upstairs are not dimmable. Yet it currently works.

If you have a look at the U-Landing-A-1 and B-1 images, you'll see how the old switch is wired up. I have taken one picture from the top and the other one from the bottom.
It has L1, L2 and C terminals (left to right).

From the lightwave website (the new smart switch brand), they say to move all wires from the L1 terminal to the L port and from L2 to the X ports on the new switch, while capping the C port off.

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.

So this is what I did as shown in the "Initial Wiring" image.
This tripped the breaker in the fuse box when I switched the power on.

So I disconnected everything ("Separated Wires" image) and decided to test each wire to see which was live with my multimeter.

There are 3 main sleeves coming from the wall. You can see I have separated the wires - left, top and right according to which sleeve it was coming from.

Anyway, have a look at the "Separated" image. I have put connector blocks on all of them and I have determined that 3 of these wires are showing about 240v on my multimeter. I have circled the ones which were showing the voltage.

I think the small brown sleeves are put on the wrong wires. Shouldn't they be on the switched live wires only?

So now, given the new 2-gang 2way lightwave switch has: one L terminal and two X terminals and one Neutral terminal, what should I wire where?

This is just the upstairs switch.

Appreciate the help on figuring out what to wire into which terminal to make the 2-way work well.


Thanks,

JH

 

[ericmark]

Not used Lightwave, with Energenie the S terminal is not 230 volt, it is a signal, so one has to be careful all S terminals together so not wired like normal two way.

However on the Lightwave page it say

The Smart Series dimmers do not use a signal cable for multiway switching so they have to be linked together using the Link Plus app.

and it continues to give step by step instructions.

So pictures of wiring don't help much, for non smart switches the on/off go com to L1 where in two way often L1 and L2 but colours mean nothing.

 

[terryplumb]

Is your first pic ( initial rewiring) a two gang ,two way switch ??
It looks identical to the two gang ,one way ,switch of your other thread ???
If the wiring is from two circuits , it's surely going to trip an RCD or RCBO ,if the wiring is interconnected ?

 

[Taylortwocities]

First off. If the two circuits are on separate lighting circuits, they cannot share the same Lightwave switch. If you try and common the lives or neutrals from different circuits all this will do is to trip any RCD in the circuits. You will probably need two separate one gang switches, not a combined two gang smart switch.

Second off, in common with many smart light switches, the two way function is not provided by a physical wire, but through an bit of separate software. It looks like Lightwave is the same. as Eric has said, you need to carefully read the very comprehensive instructions on this subject. It’s here
https://support.lightwaverf.com/hc/...-How-to-Set-up-a-Two-Way-Switching-Automation

 

[Jetheat]

Is your first pic ( initial rewiring) a two gang ,two way switch ??
It looks identical to the two gang ,one way ,switch of your other thread ???
If the wiring is from two circuits , it's surely going to trip an RCD or RCBO ,if the wiring is interconnected ?

Yes, its an identical 2-gang switch but can be used for 1-way or 2 way.
How do I stop it tripping while being on 2 different circuits?

You can have two lightwave switches on different circuits and still have it be 2-way.
I've done this downstairs with my 3-gang and 1-gang. It does work.

Just need to find out what wiring needs to be done to make it work.

JH

 

[terryplumb]

Isnt your downstairs 3 gang and 1 gang switches fed from one MCB in your consumer unit ( what you call a fuseboard) so to isolate both of them you turn off just one MCB ?

 

[flameport]

Just need to find out what wiring needs to be done to make it work.

The same as for the other switches you attempted to install, which was dragged out to 10+ pages of repeating the same thing again and again.

There are two ways to install these switches.
Either learn how switches work and follow the instructions provided by the manufacturer of the switches.
Or pay someone to install them.

 

[Jetheat]

Isnt your downstairs 3 gang and 1 gang switches fed from one MCB in your consumer unit ( what you call a fuseboard) so to isolate both of them you turn off just one MCB ?

No, two separate breakers.

But now, because of the way I have wired them to make them work, all three breakers need to be off for me to work on them.

 

[Taylortwocities]

I agree with Flameport.

There are two ways to install these switches.
Either learn how switches work and follow the instructions provided by the manufacturer of the switches.
Or pay someone to install them.

I’m out, good luck.

 

[333rocky333]

No, two separate breakers.

But now, because of the way I have wired them to make them work, all three breakers need to be off for me to work on them.

That is extremely dangerous

 

[terryplumb]

No, two separate breakers.

But now, because of the way I have wired them to make them work, all three breakers need to be off for me to work on them.

I am afraid you have gone way outside of changing some light switches and have created a potentially dangerous installation ,by interlinking 3 circuits. I too must advise you to engage an electrician to undo what you have done and re instate the safety of the installation .As soon as possible.

 

[Jetheat]

Thats what the guy at Lightwave told me to do. Because of the single L terminal on the Lightwave switches, it had to be interlinked.

JH

 

[oldbutnotdead]

You can't use that Lightwave switch safely on your installation. Full stop. The installation would require significant modification. If you carry on you may get it to work but will compromise the protection provided by the MCBs in your CU.
Best advice is stop now. There would be significant work required to make it work safely and correctly (translates as significant costs to pay someone else to do it).

 

[333rocky333]

Its a plasterboard wall, pay someone to cut in extra single boxes and fit 1 switch per circuit, even if it means 3 seperate switches it will then be safe

 

[ericmark]

You can't use that Lightwave switch safely on your installation. Full stop. The installation would require significant modification. If you carry on you may get it to work but will compromise the protection provided by the MCBs in your CU.
Best advice is stop now. There would be significant work required to make it work safely and correctly (translates as significant costs to pay someone else to do it).

I was reading the Lightwave instructions, and it says

The Smart Series dimmers do not use a signal cable for multiway switching so they have to be linked together using the Link Plus app.

So if there is no wired connection, why work it matter where the switch gets power from?

I use a remote control but in essence the second switch is no more than a mains powered remote control. But myself and @Taylortwocities have given links to the set up, and I will admit I did not realise they worked in this way, and since reading have been considering also fitting one.

So please explain why you need to have same supply for master and slave? There are a number of ways to retain two way switching when the lighting circuits have been split, Quinetic is one using the kinetic energy of the switching to send a radio signal, there are also switches that use PP3 batteries, and those which fit into the ceiling rose.

I will admit I have found even electricians move a lighting MCB to same RCD as another to stop it tripping the RCD, I can accept where the electrician was unaware of the use of two core instead of three core on the strapers and wired in error, but when they know the problem and still allow a borrowed neutral that is unforgivable, but reading the instructions that is not the case with lightwave.