Simple Light Switch Installation

Nobrow

I picked up a new remote control light switch for my apartment. Now just need someone to tell me how to connect it ...

It has two connectors on it, L in and L out. I expected 3 but what do I know. I took the current light switch off and it too has just 2 connectors. My course would appear clear enough, but for the fact that there seems to be 3 wires going into it (2 into 1 connector, and 1 into the other). Im afraid I cant recall the wire colours off-hand, but I dont think they were yellow/green, blue, etc. which I was also surprised about.

Can anyone make suggestions? I dont want to risk burning down an entire apartment block.

Thanks.

delly

Just trying to recall the last time i changed a light switch, and you should have a brown (live) and a blue (neutral). The reason there is two wires going into one connection is because it probably goes onto the next light and is wired to the same trip switch on the fuse board.

I can't recall which is which though, and if your new switch is metal, you'll have to earth it using an earth wire which the green and yellow wire.

GreeBo

sounds like it just "breaks" the live connection and doesnt give a fiddlers about neutral or earth.
can you post a pic?

Nobrow

Thanks guys.

Ill check the wire colours tonight and get back tomorrow.
Im afraid I dont think Ill be able to get a picture, at least not for several days.
Both the new and the old boxes are plastic.

The building is probably only 8 years old. I thought all modern electrics would be earthed?

So do we reckon its going to be safe enough to just rewire it like it is (with two of the lines going into one connector), so long as I match up the "in"s and the "out"s?

Thanks again.

clarkee

No neutral to the switch.
The switch "breaks the live", live IN to one side and live OUT to the light.

Cables may be of the same colour ( brown - blue ) easiest way to check,if you have a phase tester put it on one of the terminals and operate the switch, the live in (from the board) will ALWAYS be live.
To be safe when changing the swich, turn off the breaker.

Hope this is of help

Doolittle51

Nobrow wrote:

So do we reckon its going to be safe enough to just rewire it like it is (with two of the lines going into one connector), so long as I match up the "in"s and the "out"s?

Yea. Connect the two wires into 'L IN' , and the single wire to 'L OUT' (if you know what i mean) Should be grand.
Switch off the leckie first though!

Nobrow

Okay, if yis havent heard from me by this time tomorrow call for an ambulance.:eek:

Nobrow

Havent done it yet but did check the wires ... theyre all brown!? The 3 wires that enter the current switch are all brown. There are also two earth (yellow/green) wires tied into one of those little plastic terminals (presumably just to stop them flailing about and causing a short).

Borzoi

Nobrow wrote:

Havent done it yet but did check the wires ... theyre all brown!? The 3 wires that enter the current switch are all brown. There are also two earth (yellow/green) wires tied into one of those little plastic terminals (presumably just to stop them flailing about and causing a short).

That's because they're all Live wires. Lights are usually run off a ring circuit, and then fed out to each lamp via a switch.

Doolittle51 is spot on.

viking

Nobrow wrote:

There are also two earth (yellow/green) wires tied into one of those little plastic terminals (presumably just to stop them flailing about and causing a short).

...and to maintain continuity of Earth throughout your house, very important!

Normally, the earth wires are connected to the (metal) back box itself. If you are installing a metal light switch you should earth the switch itself too.

GreeBo

yeah, if you leave live or neutral wires (safely) un-connected you will probbaly notice that something no longer works
With earths you wont know until something gets live that shouldnt and someone gets zapped.
you cant really go wrong connecting earth to earth.

Lex Luthor

I'm guessing if 3 wires are brown, then 1 is the live wire into that switch, one is a live wire to another light switch but not actually live until it is connected to the 1st live wire I mentioned and the 3rd brown is to the light itself switched by the switch you are at.
Confused?

Can you confirm how many of the 3 wires actually have volatge on them using the phase tester?

FX Meister

It's fairly straight forward. The two brown wires together are the live feed to this switch and then on to the next switch. The live wire comes from either the breaker or the previous switch on the circuit, the second wire with this one continues the live circuit to the next switch. Neutral cables at the switch is considered bad practise by a lot of electricians, neutrals are only needed at the light itself. As mentioned, the earth cables are in a connector to keep continuity of the earth circuit. If your switch box is metal the should be connected to this. If your new switch is chrome or brass it will need to be earthed too. I haven't seen many lighting circuits wired in a ring as Borzoi mentioned.

davelerave

it's getting very common electricians looping the neutral at switches and running a t&e up to each light.it makes fitting lights handier but it's not 'standard practice'

Nobrow

Just to say its done, everything still works, and thanks to all.