Light Switch Wiring Problem

[Keano_1]

Hi looking for some help. Im changing a light switch for a chrome one. The light is one way and only controlled by this switch. When i took the old switch off it was two way, live to the com (red), neutral (black) to l1 and the earth to l2. The new switch is also 2 way and will only work if i wire it like that as well. Should the earth be in l2?

There is a seperate earth cable coming out of the wall and into the back box earth, i could bridge this to the chrome switch earth. Is this enough for the earthing?

Thanks

 

[Andy™]

the front of the switch will need earthing. you can take the earth from the backbox and take it to the front,or a short piece to link the 2. are you sure its an earth in L2? shouldnt be an earth there

 

[Keano_1]

Hi thanks.

Its the switch cable earth that has to be in l2 for the switch to work. If i just have live in com and neutral in l1 then the switch wont work. Both wires have charge in them but switch wont work. When i put earth from switch cable in l2 then it works. This is how the old one was wired as well. Is this right

 

[Keano_1]

Hi thanks.

Its the switch cable earth that has to be in l2 for the switch to work. If i just have live in com and neutral in l1 then the switch wont work. Both wires have charge in them but switch wont work. When i put earth from switch cable in l2 then it works. This is how the old one was wired as well. Is this right

 

[Andy™]

if it only works with the earth in L2, then must be used as a live and is wired dangerously

you also dont have a neutral in L1 either, its a switched live.

 

[kerching]

are you SURE it is an earth wire in L2!.........bare copper conductor with a bit of sleeving on it?

If so, get an Electrician in ASAP to put the CORRECT cable in

it SHOULD be a 3 core and earth cable

 

[ProDave]

+1 

there's no way an earth wire should be in L1 of a light switch.

Are you sure you are not miss understanding something?

you talked about an EARTH wire into the lug in the back box

so what makes you think you have an EARTH wire into one of the switch terminals?

 

[Andy™]

he never said anything about yellow or blue... only red black and earth... sounds like a T&E being wired badly

 

[Keano_1]

Hi ok apologies it is all coming from one cable. So red is in com. Blue is in l1 and yellow is in l2. The sleeved earth is in earth. This is ok i take it?

Sorry to cause complete confusion

 

[Keano_1]

Thanks for all your swift help. Not sure why three core and earth was used on a one way switch and thats what threw me.

 

[ProDave]

Perhaps it used to be 2 way?

 

[Keano_1]

Its in a single bedroom so not sure why it would have been but could have been. I know it used to be a dimmer switch, do they require three core and earth?

 

[Andy™]

might have been a pull switch near the bed. have a look at the light and see how the switch wire is wired there. if its a different cable, then it must go elsewhere first

 

[ProDave]

That age of wiring (green earth) it probably goes to a big central junction box. They might have just wired all the switch drops in 3c&e just in case.

 

[Keano_1]

Ok great thanks guys. Ill take a look at both. Really appreciate the help