Total electrical novice here. So I removed an outside light, and the wiring for it some time ago, due to making external alterations. I left the switch (in the garage) in place, with the wires coming into it untouched, and left the switch in the off position. Intention was to come back later and install a new light. Have bought a new PIR light, which wants a red a black and an earth.. nice and simple. So I figured just run some three core cable to the light from the switch. I took the front off the switch, and inside it is fed by three core cable.. single red and two black. The red is connected to the top of the switch, and the two blacks terminate in a block. Not sure what to do next. How do I connect up my new cable to this switch which will run to the light? Is there no earth here?
Have a look at the black that is in the middle of the 3 conductors. Is it actually a piece of black sleeving that stops where the conductor enters the grey outer and then bare copper from there?
Looks like the permanent live and neutral coming in to the switch, I would imagine it still is an earth, just sleeved black instead of G/Y, can't imagine what else it could be used for. You need to look at the other end of that cable and see what's connected to what. That metal back box definitely needs a proper earth, also the terminal screw has fell out of the switch. From the photo it does look like yet another house that has, lets be kind and say "iffy" electrics.
Looks to me like one of the blacks is probably the SL, and the other is the CPC which has been sleeved? I take it you have run a new feed to the light fitting? Any chance of a photo of the other end of the cable to the switch?
Hi guys - thanks for the replies. What 3 conductors? I will check whether either have just a black sleeve, next time I am able to switch the power off, and report back. How would I install an earth for the metal box? OR would I be better to replace with it plastic cased switch? Yes, the guy here prior to me did a lot of electrical bits and bobs. Though, I understand he was an electrician.. Please clarify SL and CPC? I have not run anything to anywhere yet. I want to run a new feed to an outside light, once someone can tell me how. The other and of that cable goes into a 4 way junction box. Where are there two holes? BTW, this photo is side on. That wiring is coming in at the top.
HNT The 3 conductors are the 3 wires (2 balcks and 1 red). I suspect the middle black is a short piece of black sleeving. For us to help you we need to know certain things about those wires. To answer your other questions above: 1 To install an earth to the box would be straightforward if the middle one of the 3 wires is just a short black sleeve. It will be an earth wire. Connect it to the brass terminal at the back of the box but sleeve it with green and yellow sleeving. 2 SL = switched live. The red wire will be the permanent live (called a switch feed) and the other black should be the switched live (goes fromt the switch to the light). 3 CPC = circuit protective conductor. Earth wire in common terms. From your questions and lack of understanding I worry you do not have the knowledge and experience to carry out this work correctly and safely. Fo us to advise so you can complete this work safely you must follow any instructions given implicitly and answer all questions accurately posting photographs where possible. Kind regards
HNT - rereading your original post, when you removed the light where were the wires connected? The black I said was a switched live might actually be a neutral. Kind regards
I removed the original light some time back. I do not recall how the original outgoing cable was wired into the switch. I have not touched any of the wires in the photo, coming in from the junction box. I need to go check for a sleeve on the blacks.
You need to tell us again that those wires are coming in from the top! We will then know it's a wind-up. Mr. HandyAndy - Really
No. The wiring enters at the bottom... Otherwise that would be a gravity defying screw... obviously. Photo of the junction box from which this switch is powered. Have coloured the relevant cable yellow:
Surely if you had a working light before and you have not altered the wiring at the switch, then that cable is twin & earth, with the centre cpc (Earth) being sleeved in black ( as suggested above) From the photo, the 'black' centre sleeve does look a little baggy compared to the other black, so could be a sleeve If that is the case, ie, the centre conductor will be bare copper, covered with black sleeving. Red = Live . Black = Nuetral To be honest, the whole installation is rough; Metal back box not earthed Why use a metal box with a plastic face plate And that junction box........ Really not good on many many levels Get a spark in, shouldn't cost too much but get it done properly as currently it's a mess I'm a diyer but my wiring doesn't look like that to be honest
Yes, the guy before me was a bit cable happy. There were a dozen plug sockets in the garden shed! (which has long gone). I imagine though, an elec will want to re-wire the whole lot when he see's it. Not sure what that will cost. i.e. he wont want to just add an outside light to the existing set up. As far as I know it is all sound. It all works, and has been in place along time. I think I will replace the switch for sure. And once I get the power off I will check that sleeve, and then post back.
Just looked at that JB again and the cable going to the switch (coloured yellow) you can clearly see the earth wire there and it's sleeved with black fabric sleeving No other earths are sleeved (as happens all too often)
Yes mate, you're right. It's frayed. OK, so if that's the earth, to cable my new light to that switch (imagining it is a nice new shiny plastic switch!) I take the live from the bottom of the switch, and the earth and neutral from the block connectors, and outside to the light, with a straight forward wire up of red, black, green/yellow into the light. (?)
I'm still worried about that junction box. There seems to be blacks connected to sheathed blacks, reds connectected to blacks, blacks connected to bare earth....... Mr. HandyAndy - Really
Agree with Andy, that JB needs checking out and all cables identified When you say a straightforward wire up of red, black to the new light, these colours are not used any more in twin & earth cable, now blue and brown + E, and have been for some years Do you have a stash of old cable lying around then ?
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