Ceiling Light Issues

[Mozlawolf]

I stupidly failed to take a picture of the original wiring and only realised afterwards that I had four earth cables and 4 black cables going to the older light fitting. The red wires were all in a connector block and tucked away in plasterboard. How do I determine what each black wire is to go to a Live and Nuetral light fitting?

 

[westward10]

Can you show a pic although without a continuity tester it may not be possible to guide you from afar.

 

[Baddegg]

Red sleeves indicating ya switched lines or test gear mate I’m afraid, any pics?

bloody hell youre quick @westward ?

 

[Mozlawolf]

Can you show a pic although without a continuity tester it may not be possible to guide you from afar.

Please see the attached picture! Thanks for the quick reply - I also have a multimeter. The four black wires were attached to the old light fitting and the red wires were in a connector block stuffed into the ceiling. I tried to send a brown wire from the red connector block to the live terminal on my new light fitting and a blue wire from the black wires and the light came on (when light switch was off) - when I flipped the switch this tripped the lighting circuit.

 

[westward10]

Only three of the blacks are neutral the other is the live return from the switch. You should have continuity between the reds at the connector when the switch is on and one of the blacks only, that is your live.

 

[Mozlawolf]

Only three of the blacks are neutral the other is the live return from the switch. You should have continuity between the reds at the connector when the switch is on and one of the blacks only, that is your live.

Thanks really appreciate this! What setting on Ohms should I set my multimeter to? Do I connect the black multimeter clip to one of the black wires and then the red one to the corresponding red wire? What should I look for on the multimeter screen - will the number go high on the switched live cable?

 

[westward10]

Put it on 200 ohm. Leave reds all connected together and test each black to the reds until you get continuity. Get someone to turn the switch on and off and you will get a reading when on. Only one will do this and it doesn't matter which way the meter leads go but ensure POWER IS OFF.

 

[Mozlawolf]

Good news - finally sorted it! The black wire that changed its value when the light was in on position was the live switch wire and the others in neutral worked perfectly! Thank you so much for everyone’s help!

 

[westward10]

No worries glad to help.

 

[Baddegg]

Good news - finally sorted it! The black wire that changed its value when the light was in on position was the live switch wire and the others in neutral worked perfectly! Thank you so much for everyone’s help!

Good work!...put a red sleeve on it for the next poor sod! ?

 

[Mozlawolf]

Good work!...put a red sleeve on it for the next poor sod! ?

All sorted! Put some red tape on it!! Can’t believe the last person didn’t do it in the first place!!