Use Existing Light to Power Security Light?

[Foresty Forest]

I want to install an exterior security light on the extension. Is a LED with sensor. Could I add a junction just before this light in the coal shed, and run a wire from it out through the eaves to the security light?

 

[AndyPRK]

take a pic from the other side, showing :

1) how many cables going to the light
2) what the grey/white box is all about

 

[Foresty Forest]

This is all there is. Wire leading into light bulb. Wire leading out to the switch. That white box is just something leftover from when there was a boiler here - definitely dead.

I'm wondering if it's possible to wire a junction into the wire leading to the light?

 

[winston1]

I'm wondering if it's possible to wire a junction into the wire leading to the light?

It is possible of course but not the right thing to do. If you do you will have to have the coal shed light shed on all the time you need the security light to operate.

EDIT. Just seen your picture with two wires to the light. Connect to the wire leading to the light that does not come from the switch. Rather than using a junction box connect the wire to the light itself. Use 1.0mm twin and earth.

 

[Foresty Forest]

you will have to have the coal shed light shed on all the time you need the security light to operate.

I'm guessing that'll be because the circuit wouldn't be complete otherwise?

What about if I installed a double socket, and add plugs to both lights and powered them like that?

 

[Sureitsoff?]

as winston says connect your new light to the same terminals in the light fitting that the cable NOT coming from the switch is connected to. inside the light fitting is like a junction box anyway and that particular light fitting has a nice deep recess for cabling. the outer ring unscrews(the bottom bit nearest the joist) the lampholder will drop, it is connect to the base by two wire and you will see the connections. best to do this with the power off not just the switch. here is what the inside looks like

 

[Foresty Forest]

as winston says connect your new light to the same terminals in the light fitting that the cable NOT coming from the switch is connected to. inside the light fitting is like a junction box anyway and that particular light fitting has a nice deep recess for cabling. the outer ring unscrews(the bottom bit nearest the joist) the lampholder will drop, it is connect to the base by two wire and you will see the connections. best to do this with the power off not just the switch

Ok does that mean I won't need to leave the light on as Winston also says?

 

[Sureitsoff?]

yes, if you connect to the same terminals as the cable not from the switch the power to the new light will always be on but you could put a switch in the feed to the new light so you could turn it off if you wanted to, ie between the old light fitting and the new one

 

[Foresty Forest]

So in this case I'd connect the security light live to the terminal with both live wires? And neutral to the neutral side used by the incoming wire?

 

[AndyPRK]

connect live wire to the middle terminal block (there is a spare hole)
connect neutral to the right terminal block (there is a spare hole)

 

[bernardgreen]

Sorry it is a rough drawing.

 

[Sureitsoff?]

bernard , from your sketch you are assuming that the switched live has been put in the "correct" terminal in the rose.

 

[bernardgreen]

from your sketch you are assuming that the switched live has been put in the "correct" terminal in the rose.

Yes I am making that assumption. No doubt the OP will come back if it doesn't work.

 

[Foresty Forest]

It's worked a treat. Thanks for the advice. Now I don't have to do the bins in the dark...