Electrical wiring and light fitting- confused

[Taffery]

Hello,

I went to replace a bathroom light. When removing the old light I discovered there were more wires than expected attached. I
Don't know what order they were in. They come from three electrical cables and in total there are 3 black one green and one green and yellow...??
Power to light is off. What should I do? 

 

[Taffery]

https://www.flickr.com/gp/53018374@N04/f79M3d

 

[Sharpend]

Any red cables? 

 

[Taffery]

Yes but they don't protrude through the hole. They are above the ceiling but visable. 

? 

 

[Manator]

Hi Taffery, you will have a power in and a power out (loop) and a switch wire. Without test equipment it would be a case of trial and error to get them right. One of the black cables will be paired with one of the red to form the switch wire. Is there any marking on any of the black cables?

If there is then you are in luck as that would be the switch cable and goes into the LOOP with the red cables, the paired red would go to the lamps LIVE out.

 

[Taffery]

Right...

so should I pull the red through too? 

Is it two black in to light together , green together and one of the black to the red? 

Did the photo help? 

 

[Sharpend]

Take a look at the black cables, are any two bent in the same manner/pattern? 

It sounds as though the reds are all permanent live (live in live out and live to switch) you will then have two blacks to neutral and a single black to live of pendant/light. 

If you can determine by looking which two blacks go together then you're half way there. 

 

[Evans Electric]

Do you have a neon screwdriver ?  Can you borrow one ?  

If you can ,  take great care and follow this .

Seperate the wires .

Restore the power .

Taking great care, touch nothing with your fingers .

Get someone to switch the light switch on & off ...on & off  and hold the screwdriver on each black cable until you find one of them is flashing the neon on & off .......note which wire this is.

Turn off the power .

Mark that wire with some tape .

Reconnect fitting by putting the two unmarked blacks together in the N terminal ...and the taped one in the L terminal.

All earths  ( greens) in the E terminal.

Job done.

 

[Taffery]

Ok. Thanks guys I'll give it a go. thNks for your help. 

 

[doormatt26]

Make sure you put the green and yellow and the 2 cores in the green sleeving together in the earth terminal on the light if it is a class 1. If no earth terminal make sure you still connect these cables together. These are for safety and won't effect the working of the light but may save your life. 

 

[Sharpend]

Just seen the photo, is that one of the black cables with a white mark on it or is the mark just plaster? 

Looking at the pic I'd be inclined to say the two cables which have the earths in the green sleeve are possibly the loop in/out cables. Drop the switch off the wall and check the earth sleeving there, if green/yellow then is it possible that the switch had been moved at some point from its original position? 

 

[Andy™]

typical DIYer, jumps straight in ripping the old down then thinks about how he's going to connect the wiring to the new one...

the number of wires there is normal, almost all lights will have this

since you dont know the switch wire, you will need to find out which one it is. this will take seconds with the correct test equipment... or even less time to identify it before disconnecting everything...

 

[Doc Hudson]

Make sure you put the green and yellow and the 2 cores in the green sleeving together in the earth terminal on the light if it is a class 1. If no earth terminal make sure you still connect these cables together. These are for safety and won't effect the working of the light but may save your life. 

This is a very important point highlighted here. If this part is not done correctly, although your lights may all appear to be working, other fittings further along the circuit may have no earth continuity. Which in the event of a fault could be a serious danger of electric shock.

Doc H

 

[shieldssecurity]

Hello,

I went to replace a bathroom light. When removing the old light I discovered there were more wires than expected attached. I
Don't know what order they were in. They come from three electrical cables and in total there are 3 black one green and one green and yellow...??
Power to light is off. What should I do? 

If I had a £

 

[Taffery]

It's all sorted now thanks everyone. Don't worry about the earths either. 

Especially 'Evans Electric' -very helpful.

Oh, thanks Andy - very helpful comments....