Replace double pole light switch with smart switch

[naik420]

Hi
I have a double pole switch that switches on and off the outside lights under guttering area (front side and rear of the house all operated by this one switch). I see 2 Live cables in L1 and another red non-Live cable in L2 which becomes live when the switch is turned on. There are 2 black neutral cables in N1 and 1 in N2. None of the neutral cables becomes Live when the switch is turned on.

I tried to take out the L2 cable and none of the outside lights turned on. I’m not sure how to replace this switch with a smart switch (I have the no neutral cable switch).

Can you help?
Thanks

 

[timhoward]

In fact you don't need the "no neutral cable" switch as you have a neutral at the switch.

Basically the wires in L1 and N1 are the lighting circuit supply coming in and going out. to the next light somewhere.
The cables in L2 and N2 get joined to these if the switch is closed.
There isn't usually any need to switch both the line and neutral to the light(s) so the wire in N2 could equally be in N1.

So in summary there is a group of wires that are Neutral (N1), a group of wires that are permanently live (L1), and one wire (in L2) that is switched live. That summary should correlate to the instructions for your smart switch.
(I'd also have to advise double checking the load of the lighting, and that it is within the rating of the smart switch.)

If in any doubt how to proceed then get some help in.

 

[naik420]

In fact you don't need the "no neutral cable" switch as you have a neutral at the switch.

Basically the wires in L1 and N1 are the lighting circuit supply coming in and going out. to the next light somewhere.
The cables in L2 and N2 get joined to these if the switch is closed.
There isn't usually any need to switch both the line and neutral to the light(s) so the wire in N2 could equally be in N1.

So in summary there is a group of wires that are Neutral (N1), a group of wires that are permanently live (L1), and one wire (in L2) that is switched live. That summary should correlate to the instructions for your smart switch.
(I'd also have to advise double checking the load of the lighting, and that it is within the rating of the smart switch.)

If in any doubt how to proceed then get some help in.

Hi Tim

Many thanks, this makes sense. So on the smart switch I have L, L1, L2, L3 (I have a 3 gang smart switch - photo added). Am I correct in saying that I can connect all neutrals to any or all of L1, L2, L3 terminals, and the live to L? Will it be ok to connect L2 on old switch to L of the smart switch as well?

Thanks for your help.

 

[timhoward]

NO! Stop!
I’m sorry but I’m I’m not going to advise you how to wire up the new switch as I’d want it in front of me. If it isn’t evident from the instructions and my description of your old wiring then you need help.
I will say that what you suggested is dangerous, please don’t do it.

 

[littlespark]

Basically don’t connect anything that was an N into any connection marked L

You will at the very least trip a breaker…. At most, destroy the smart switch.

 

[brianmoooore]

You have a 3 gang smart switch. Presumably, your idea is to split the lights between three switches, so that they don't have to be all on at the same time.
Unfortunately, this is not possible with the wiring that you have. You will only be able to use one gang of the smart switch, and the lights will all switch on and off together, as before.

 

[naik420]

You have a 3 gang smart switch. Presumably, your idea is to split the lights between three switches, so that they don't have to be all on at the same time.
Unfortunately, this is not possible with the wiring that you have. You will only be able to use one gang of the smart switch, and the lights will all switch on and off together, as before.

Hi Tim

Many thanks, this makes sense. So on the smart switch I have L, L1, L2, L3 (I have a 3 gang smart switch - photo added). Am I correct in saying that I can connect all neutrals to any or all of L1, L2, L3 terminals, and the live to L? Will it be ok to connect L2 on old switch to L of the smart switch as well?

Thanks for your help.View attachment 99597

Thank you all. Finally I would just ask if it is possible to replace the old double pole switch per the photo I previously shared in my original post with the smart switch per the post I’m replying to, and that is without serious danger. I’m good at diy but cautious where I need pro help.

would be great if you can advise which wire may go where from the old DP switch to new smart switch.

Many thanks for your replies and help!

 

[naik420]

NO! Stop!
I’m sorry but I’m I’m not going to advise you how to wire up the new switch as I’d want it in front of me. If it isn’t evident from the instructions and my description of your old wiring then you need help.
I will say that what you suggested is dangerous, please don’t do it.

Hi Tim
Apologies, I totally misread your response. I’ll give one last try or her help. Will it be ok to connect all the neutral cables from N1 and N2 together outside of the smart switch; attach the true Live cables from L1 of DP switch to L of smart switch and the switched Live cables from L2 of old DP switch to, say, L1 of the smart switch?

 

[naik420]

Basically don’t connect anything that was an N into any connection marked L

You will at the very least trip a breaker…. At most, destroy the smart switch.

Thanks, this clarifies and helps