Figuring out lighting wiring

[joe384]

Hi, I am trying to figure out some lighting wiring.

This is a 4 gang switch I have at the base of my stairs.



Running from left to right:
Switch 1 - two way switch for landing: Grey wire with brown sheathing - L2, Brown - L1, Black with brown sheathing - COM
Switch 2 - Another two way switch for lounge: Same as switch 1
Switch 3 - Hall light: Brown - COM, Brown - L1
Switch 4 - Porch light: 2 blue wires+ grey with blue sheathing - Loop, brown - COM, Brown with brown sheathing - L1

Now switch 1 and 2 on the left are both 2 way switches, but I am a bit confused what is happening with the others - There is some looping going on (but only neutral?) and 3 and 4 are sharing a live on their commons (assuming the colours are correct)

What is odd is that at the ceiling roses there is no looping going on - The hall light, porch light and lounge lights all have a single twin and earth dropping down.

I guess there must be some junction boxes hidden in the ceiling somewhere, but I just can't get my head around how it might be wired! I've looked at some guides online but it seems that there is a bit of a mashup going on here.

The reason for all this is I was looking at adding a few shelly L1's to be able to control some of the lights.

At a guess I can use the COM on 3/4 as a Live for the shelly, N Loop as a neutral and the switched live of the light I want to control go to the output on the shelly.

 

[ericmark]

Neither can I from the picture, some manufacturers use same casing for a range of switches, so with a grid switch one may be a on/off, next two way, next intermediate, and next double pole. Not saying that is what you have, but does look as if right hand switch is a double pole and two left hand switches two way and remaining switch on/off which is easy to do with grid switches.

 

[joe384]

The switch is a Hager, each gang has four connections, com, loop, l1, l2 I believe.

I think I have figured out what is going on though now. If we focus on the 2 right hand switches I think there is a live and neutral supply cable coming down to the switch and then a cable for each light. So the 3 neutrals are 1 for each light and the supply one. The supply live is shared and you are left with 2 switched lives for each switch on the right.

 

[SUNRAY]

The switch is a Hager, each gang has four connections, com, loop, l1, l2 I believe.

I think I have figured out what is going on though now. If we focus on the 2 right hand switches I think there is a live and neutral supply cable coming down to the switch and then a cable for each light. So the 3 neutrals are 1 for each light and the supply one. The supply live is shared and you are left with 2 switched lives for each switch on the right.

Yes
All that's happened is the installer has used a 'spare' terminal for the neutral junction.
A method which will be frowned upon by some on here.

 

[Pdeemo]

What you have are Hager switches with a neutral loop connection. Used for having the neutral at the switches as many new lighting fittings do not have a facility for 3 plate wiring.
So basically you have standard two way light switches with an extra connection for neutral loops. Dangerous in the wrong hands.

 

[winston1]

[QUOTE="SUNRAY, post: 5108162, member: 124249"

A method which will be frowned upon by some on here.[/QUOTE]
Why. That is what it is for. It is even labelled loop.

 

[sparkwright]

'N loop' in fact.

 

[SUNRAY]

Looking at this now on a better screen I can see the 'N LOOP' marking so yes this is totally pukka.

Not being able to read the markings earlier (as I suspect was also the case with Eric, from his comment) I fell into the trap of assuming these are intermediate switches, and added to that I saw mention of intermediates.

My apologies for my error and thanks to to others for correcting the information. to OP

 

[sparkwright]

Looking at this now on a better screen I can see the 'N LOOP' marking so yes this is totally pukka.

Not being able to read the markings earlier (as I suspect was also the case with Eric, from his comment) I fell into the trap of assuming these are intermediate switches, and added to that I saw mention of intermediates.

My apologies for my error and thanks to to others for correcting the information. to OP

I have seen, and I think this may be what you were talking about earlier, people using a 'live' terminal on a switch to accommodate the neutral.

For example - a 2 way switch used for 1 way operation.
one switch live in COM
one permanent live in L1
both neutrals in L2.

It doesn't blow the fuse, as the switch will be in two states;
switch live and perm live making contact, light comes on.
switch live and neutral making contact - won't blow the fuse, light is off.

Think this is the kind of thing you were referring to, a very lazy, yet still quite clever, way of joining the neutrals if you haven't got a connector block.

 

[SUNRAY]

I have seen, and I think this may be what you were talking about earlier, people using a 'live' terminal on a switch to accommodate the neutral.

For example - a 2 way switch used for 1 way operation.
one switch live in COM
one permanent live in L1
both neutrals in L2.

It doesn't blow the fuse, as the switch will be in two states;
switch live and perm live making contact, light comes on.
switch live and neutral making contact - won't blow the fuse, light is off.

Think this is the kind of thing you were referring to, a very lazy, yet still quite clever, way of joining the neutrals if you haven't got a connector block.

Yes that is precisely the way I thought it had been wired, however when I viewed it on a phone it looked like intermediate switches. It's actually a fairly common method however I've seen it condemmed a few time on this forum a dangerous as some seem to think the L1 & L2 can arc across..