Smart switch advice please

j1000 · Post by **j1000** » Thu Nov 19, 2020 10:30 pm

Hello, i hope you are well.

I need some advice please if possible.

I have a 1 gang light switch which controls 2 external porch lights.

I would like to install a smart light switch and need to know which one to purchase.

I have turned off the electric breaker which controls the circuit and undone the switch.

I can see there is 2 brown wires (Live), one which goes into com and the other goes into L1.

The 2 blue wires (neutral) are joined together in a coupler. Also an earth (green/ yellow).

Can anyone help by letting me know if a smart light switch would work and which one to purchase please?

I have another scenario where I have another 1 gang switch which controls some outdoor fascia lights.

Again behind the light switch is a single brown (live) and single blue (neutral) wire (also earth).

Again, is this controllable with a smart light switch? and which one is bets to go for?

Any help would be most appreciated.

Kind regards.

Someone-Else · Post by **Someone-Else** » Thu Nov 19, 2020 11:13 pm

You may want to read a post we wrote some time ago regarding smart light switches Click here

But any questions, please post here.

j1000 · Post by **j1000** » Fri Nov 20, 2020 8:24 am

Thanks for the reply.

I would like to understand are the wires behined my switch either live and neutral or live and switched live?

From my understanding a double core wire has a live, neutral and earth.

Can someone explain what i possiblly have as you can purchase smart switches with neutral or without neutral and I need some advice or explanation prior to purchase.

Thanks for your help.

Someone-Else · Post by **Someone-Else** » Fri Nov 20, 2020 9:26 am

Believe it or not but in lighting, the colour of wires has nothing to do with what it is.
The reason is, it is the choice of who ever installed it as to what colour does what.

With a "normal" switch it only needs live and switched live, but it is often too much hassle to buy / carry round a "twin red" or "twin brown" cable, so the "normal" coloured cable is used. You are supposed to sleeve the "wrong colour" to indicate that it is a switched cable, but most folk do not bother.

Below is a Twin brown cable

: TB.jpg (3.94 KiB) Viewed 1341 times

Below is a Twin red cable

: TR.jpg (9.32 KiB) Viewed 1341 times

So your statement:

j1000 wrote: ↑Fri Nov 20, 2020 8:24 amFrom my understanding a double core* wire has a live, neutral and earth.

Really depends on what colours who ever installed it chose to use and what is at each end of the cable. Since sockets do not require switched anything it is 99.9% probable one is live the other is neutral, but in lighting, if you have just a twin and earth at a light switch, it is 95% probable that one is live the other is switched live (But it has been known for them to be incorrectly wired at the other end and be live and neutral, resulting in a bang/flash when the switch is operated. (We get that problem quite often on this forum.)

From what you have said regarding what you have behind your switches, you have one of each scenario.
One has just live and switched live, the other has live and switched live and loop in neutral*.

* It is called twin and earth, not double core, as it actually has 3 cores, as you said.

* Looping the neutral at the switch is becoming more common due to the advent of smart switches which require a neutral.

j1000 · Post by **j1000** » Fri Nov 20, 2020 1:22 pm

Thanks for the detailed explanation.

Really appreciate your reply.