Replace an existing outside light

[markbramley]

Hi There,

Calling on all you expert electricians out there!!

I have recently tried to replace an external light one that has a blue, brown and earth wire and connect this to the mains supply which has no less than 6 wires. 2 black, 2 red and 2 earth coming from 2 seperate cables. I assume the reason for so many mains wires is that the light outside is connected to a switch indoors that has two switches (not sure though ). I connected to the mains supply using the terminal block that was in the old light fitting putting 2 red in one side of it to the brown wire in the new and 2 black in one side to the blue of the other. When I switched the electricity back on it shorted at the consumer unit. Does anyone know why and how I connect these 6 mains supply wires into the 3 on the light??

Please help . it must be possible because the old one used to work that only had 3 wires in it!!

Many Thanks

Mark

 

[londonboy]

One of those cables will go to a switch.

So one of those blacks isnt a neutral, its a switch line.

Use a multimeter and look for continuity between red and black (with switch in the on position)

 

[markbramley]

One of those cables will go to a switch.

So one of those blacks isnt a neutral, its a switch line.

Use a multimeter and look for continuity between red and black (with switch in the on position)

Thanks for your advice!! Appreciate it!!

is there anyway you can somehow illustrate how you would wire up this light??

Cheers

 

[londonboy]

At the top of the page click the wiki tab and look for 1 way lighting

 

[markbramley]

At the top of the page click the wiki tab and look for 1 way lighting

Hey.

Have found the diagram and can see the problem. I need to know which of the two wires is the mains supply and the other the switch, this way I can ensure the ring isn't broken. In addition the old light was fitted using a ceiling rose which is similar to that of the diagram. The new light is one that is situated on the wall using only a single terminal block hence why I need to use something like the ceiling rose that can accomodate the additional wires in the circuit. By using only one terminal block including mains, switch one side to the light on the other is too much. Can I use more than one terminal block and recreate the circuit in the diagram?

Hopefully that sounds reasonable?!?

Thanks

 

[ban-all-sheds]

 

[markbramley]

Thanks for your help!!

I'm a little confused tho cos I have only got two main grey wires. One for the mains supply and the other for the switch. In this diagram there are three grey wires. In my case both grey wires contain a red, black and an earth wire.

Starting from scratch cos I have already taken out all the wires from the rose, I need to do the following (correct me if I'm wrong)

1) Wire the BLACK cable(switch) into the diagrams taped up terminal block as well as the RED (mains supply).

2) Connect the remaining RED live wire (switch) into the L section of the light fittings terminal block that is connected with a BLUE wire going to the new lamp.

3) Connect the BLACK neutral wire (mains) into the N section of the new light fittings terminal block that is connected with a BROWN wire going to the new lamp.

3) Connect both EARTH wires from the (mains) and (switch) into the light fittings terminal block marked E that has the GREEN and YELLOW wire going to the new lamp.

In essence I had 6 wires at the start. Following the above all 6 have been accounted for Is this the correct way of wiring??

Thanks again for your help, I really appreciate it..

 

[ban-all-sheds]

It will work, but it isn't correct.

Re 1 & 2 - it's usual for the switch cable to have permanent live on red and switched live on black. No less safe the other way round, nor any less confusing as long as you sleeve the black red at each end.

What is more wrong is in 2 & 3 - you need to learn what the new colours are for Live & Neutral.

 

[markbramley]

It will work, but it isn't correct.

Re 1 & 2 - it's usual for the switch cable to have permanent live on red and switched live on black. No less safe the other way round, nor any less confusing as long as you sleeve the black red at each end.

What is more wrong is in 2 & 3 - you need to learn what the new colours are for Live & Neutral.

Hi, my mistake - Live is Brown and Blue Neutral..

Sleeve black red at each end - what does this mean??

I have also noted that the switched live in my process is going to the block that is taped up. Should this not be in the lamp so that it goes on and off at the switch?

Regards

 

[ban-all-sheds]

Given this if I connect the wires up using the correct colours i.e. remaining red goes to brown and black to blue in the new lamp would it work as like I described in earlier mail as I do not have third grey cable?

Yup.

This third grey cable I'm guessing is the feed to the next light which is not required here.

Correct.

Sleeve black red at each end - what does this mean??

You might struggle to find red sleeving in the shops these days though - use brown if you can't get red.

 

[markbramley]

Given this if I connect the wires up using the correct colours i.e. remaining red goes to brown and black to blue in the new lamp would it work as like I described in earlier mail as I do not have third grey cable?

Yup.

This third grey cable I'm guessing is the feed to the next light which is not required here.

Correct.

Sleeve black red at each end - what does this mean??

You might struggle to find red sleeving in the shops these days though - use brown if you can't get red.

Finally, the black switch wire in my process is connected to the block taped up. Should this not be going to the Live in the lamps terminal block and replaced with the switch red cable in the taped up block?

If permanent live is in the lamp as opposed to the switch wire, does this mean the lamp will be on constantly?

Thanks

 

[ban-all-sheds]

Finally, the black switch wire in my process is connected to the block taped up. Should this not be going to the Live in the lamps terminal block and replaced with the switch red cable in the taped up block?

That's the conventional way round.

If permanent live is in the lamp as opposed to the switch wire, does this mean the lamp will be on constantly?

Yes.