Incorrectly wired security light

funkey_monkey

At the rear of my house there is a PIR security light overlooking the garage pedestrian door and oil tank. This light has been daisy-chained with some soffit lights into a 6 gang 2-way light switch at the back door of my house. This 6 gang switch controls all exterior lighting at the sides and rear of the property and rear hallway/porch. There is a 4 gang switch at front door for the front hall and front lights.

This isn't ideal as I can't leave the PIR security light on without having the soffit lights on. I'm trying to figure out the best way to separate these out so that I can control the PIR security light independently.

The simplest thing to do which would mean no rewiring is to convert the soffit lights PIR equivalents. However, I'm not keen on that idea as we have enough PIR lights around the house and they are in an area where rabbits and neighbours cat frequents, so there would be numerous false activations. I have a strong preference to have the soffit lights and this PIR security light separately controlled.

I thought about separating out the PIR security light and wiring it into a free gang in the 6 gang faceplate. However, the electrician only fed 2 conduits into the backbox and they already have 3 t+e going down each conduit, so insufficient space for another cable.

My next thought was to control the PIR by converting the 1 gang garage light switch to a 2 gang switch and diverting the feed from the PIR security light to this switch. This back box is supplied with 3 t+e. First is a cable out to the lights (2 daisy-chained LED batons), second is I presume the power and third is unused in the faceplate and cut inside the garage access with little excess remaining. I'm not sure what was the thinking with the third. I'm guessing the fella pulling the cables forgot about daisy chaining the lights and thought about having separate feeds.

In the back box, earths are connected, neutrals are connected and lives are switched. Spare cable is totally unused.

So, what I'm thinking of doing is as said above - change the faceplate to 2 gang and connect the PIR security light into this faceplate. However, what I'd like to do is to pull the PIR security light cable down into the backbox rather than using the existing cable, if at all possible in order to avoid a junction box and the unknown spare t+e.

I've no visibility of the conduit entering the garage attic as there is a joist in the way. I think looking at it that it would be a tricky path to pull to get it into the conduit. Is there any way to successfully pull the cable down using the existing spare cable? My method of pulling t+e with another t+e would probably not be streamlined enough to get around joist.

Any suggestions as to how I could pull this in or an alternative solution?

1. Add PIR soffit lights
2. Join the PIR security light into spare t+e in garage and trust it is okay for use
3. Pull PIR security light cable down to faceplate in garage
4. A way of utilising the spare gang of the 6 gang switch at back door where all other related switches are located
5. Another idea

funkey_monkey

Is there anything I could do by feeding a switched live single down the conduit at the 6 gang switch? I'd still have to get common earth and neutrals though which could be messy.

Edit: intercept the live feed to the switch in attic and join the PIR security light neutral and earth there. Live from the PIR security light goes to back box using a single.

It would work, but is it acceptable practice as there would be a junction where the PIR security light meets the soffit lights (to extend the cable over to the switch) and again above the 6 gang switch.

funkey_monkey

Is anyone able to help me out here?

Doolittle51

https://www.boards.ie/discussion/comment/122623055#Comment_122623055

There's a lot of detail in your opening post & quite confusing to read.

If possible, one solution would be to bridge out the switch at the back door, then break into the (now permanent) live feed to the soffit lights with a t&e brown/brown wired back to a new switch, possibly located somewhere else.

Open to correction, afaik, singles are no longer permitted, all cables need to have an earth core. Otherwise you could probably get a single core brown down the existing conduit and use it for the permanent live to the security light.

funkey_monkey

The feeding of a single core brown into the existing hand switch is my preferred option.

Gleefully someone can confirm its legality.

Doolittle51

I wouldn't be very worried about a single core brown run alongside, maybe cable tied to, the existing t&e. 'Legal' or not, it definitely won't be the worst breach of rules in your house, I'm sure upon close inspection, there are far worse issues.

funkey_monkey

https://www.boards.ie/discussion/comment/122635416#Comment_122635416

I hope not as it is only a few years old.

funkey_monkey

I'd only be running the single from a junction box above the switch down the conduit into the switch.