I changed ceiling light and it won’t light up!

[Timmymeads]

I decided to change my ceiling light for a new one. A simple x4 bulb horizontal fixture.
I didn’t look at the previous wiring on old light and then realised there were

X4 black wires
X4 red Wires
Earth

coming out the cieling.

I assumed I put all black to neutral and red to live and Earth to Earth in the light fixture but I did this and ALL lights would stay on.

I was a little clueless. I did research on google which said to find the black (live wire) by connect block x4 red and seperate connect x3 black and leave a x1 black out. Until the electric box doesn’t pop then put that black live wire into the live cable of the lamp. Then join a cable from other x3 black wires to the neutral. I did this and light in kitchen lighted up but didn’t switch off. All the other lights on the circuits was off... I then figured by putting x2 black in a connection block and x2 other black in connection block aswell as the 4 red in connection block. I had light everywhere again but the light in kitchen although I have not connected it but how would I do that!? I’ve spent hours trying to figure out how it would work!! I also think the red wires might not have been catching in the block or not straight enough perhaps? To which eventually I got light back in the rest of the house? Or would I always have light given all red together and the x3 black with x1 black live discarded. Any help would be appreciated. On the circuit I have x3 sets of lights I think and possibly the alarm system.

Thank you

 

[freddo]

You need to call an electrician. Swapping wires about and resetting things until the 'electric box doesn’t pop' is reckless and will likely result in damage to at least some part of the circuit. The light switch is almost certainly damaged, if not totally destroyed.

Fault finding requires methodical testing using test equipment, and could have been safely carried out with the supply isolated.

 

[Timmymeads]

You need to call an electrician. Swapping wires about and resetting things until the 'electric box doesn’t pop' is reckless and will likely result in damage to at least some part of the circuit. The light switch is almost certainly damaged, if not totally destroyed.

Fault finding requires methodical testing using test equipment, and could have been safely carried out with the supply isolated.

I don’t believe any damage has been done to circuit as all light function correctly just not at the same time. How would I eliminate which wires are for which? With testing lamps? Do I connect the red and black together in the light switch then test blacks and reds? When electric off? AlsoI believe my alarm system adjacent to the kitchen with a small light are not lit too.

 

[littlespark]

I don’t believe any damage has been done to circuit

you have, mate. Maybe not apparent yet, but something has had an almighty belt across it. Maybe not the switch, but the circuit breaker, or the cable.

It would take an electrician an hour to fix it, plus maybe a replacement breaker. Trouble is finding one that only charges a 1 hour minimum.

 

[MJPD29]

I don't usually say this but just call someone out and pay them. What you are doing is incredibly careless and just dangerous. Either that or buy yourself a voltage indicator which is not a neon screwdriver and educate yourself on how to use it.

 

[Pete999]

I decided to change my ceiling light for a new one. A simple x4 bulb horizontal fixture.
I didn’t look at the previous wiring on old light and then realised there were

X4 black wires
X4 red Wires
Earth

coming out the cieling.

I assumed I put all black to neutral and red to live and Earth to Earth in the light fixture but I did this and ALL lights would stay on.

I was a little clueless. I did research on google which said to find the black (live wire) by connect block x4 red and seperate connect x3 black and leave a x1 black out. Until the electric box doesn’t pop then put that black live wire into the live cable of the lamp. Then join a cable from other x3 black wires to the neutral. I did this and light in kitchen lighted up but didn’t switch off. All the other lights on the circuits was off... I then figured by putting x2 black in a connection block and x2 other black in connection block aswell as the 4 red in connection block. I had light everywhere again but the light in kitchen although I have not connected it but how would I do that!? I’ve spent hours trying to figure out how it would work!! I also think the red wires might not have been catching in the block or not straight enough perhaps? To which eventually I got light back in the rest of the house? Or would I always have light given all red together and the x3 black with x1 black live discarded. Any help would be appreciated. On the circuit I have x3 sets of lights I think and possibly the alarm system.

Thank you

One of the cables at the light position is a L and SL it should be an easy fix for an electrician with the right test equipment.

 

[robd]

5 minute job for someone who knows what they're doing, would take me longer to talk you through how to do it than it would to actually do it. You really need a tester to identify which of the wires is the switch wire, without that you're just guessing and seriously just keeping on blowing it up is a bit mad for me. Good luck

 

[davesparks]

I don’t believe any damage has been done to circuit as all light function correctly just not at the same time. How would I eliminate which wires are for which? With testing lamps? Do I connect the red and black together in the light switch then test blacks and reds? When electric off? AlsoI believe my alarm system adjacent to the kitchen with a small light are not lit too.

The problem is that you needed to identify and label each conductor before taking the old light down, failing to do this has left you with a problem.

You need to test each cable to identify its function. Having four cables is unusual, it is normally 3.

What test equipment do you have?

 

[Timmymeads]

The problem is that you needed to identify and label each conductor before taking the old light down, failing to do this has left you with a problem.

You need to test each cable to identify its function. Having four cables is unusual, it is normally 3.

What test equipment do you have?
i have a volt pen only. I know which cable is the switch black live wire

The problem is that you needed to identify and label each conductor before taking the old light down, failing to do this has left you with a problem.

You need to test each cable to identify its function. Having four cables is unusual, it is normally 3.

What test equipment do you have?

Hi Dave thanks for help - I have only a volt pen - I think i know which is the live black wire for the light as i elimtated the x4 blacks together and x1 black out - Is this correct?

 

[peterhyper]

Timmymeads, As already suggested, call an electrician. Is money really that tight that you can't afford to pay an electrician to make it safe, or is it that you just don't want to part with your money?

 

[Timmymeads]

Timmymeads, As already suggested, call an electrician. Is money really that tight that you can't afford to pay an electrician to make it safe, or is it that you just don't want to part with your money?

Hi Peter, money isn't tight mate although my pride is, so happy to learn from you guys and fix it myself - if I need to get the right equipment then fine - I feel im 80% there - I know the was x2 connection block only hanging out the cieling with (x4 black x4 black wires.....) i cant remember where they went. There is x5 areas of lighting plus an alarm system - Currently all areas work other than alarm and light in the cupboard under stairs with the alarm. Obviously I dont know whether the light in kitchen will work as its currently not connected.

 

[peterhyper]

Hi Peter, money isn't tight mate although my pride is, so happy to learn from you guys and fix it myself - if I need to get the right equipment then fine - I feel im 80% there - I know the was x2 connection block only hanging out the cieling with (x4 black x4 black wires.....) i cant remember where they went. There is x5 areas of lighting plus an alarm system - Currently all areas work other than alarm and light in the cupboard under stairs with the alarm. Obviously I dont know whether the light in kitchen will work as its currently not connected.

.

This is the right equipment:

 

[davesparks]

Hi Dave thanks for help - I have only a volt pen - I think i know which is the live black wire for the light as i elimtated the x4 blacks together and x1 black out - Is this correct?

Do not use a 'volt pen' for testing isolation, they are a rough guide at best and not suitable for testing.

I don't know if that is correct or not as I have not seen your installation and do not know how it is wired, there are many ways to wire a lighting circuit and whilst it is likely that there is one black switched live I cannot guarantee this.

Without a continuity tester and the knowledge to use it it is not possible to identify the cables safely and without making them live.
[automerge]1580892383[/automerge]

.

This is the right equipment:

View attachment 55574

That's ridiculously over the top for identifying a few cables to replace an existing light fitting.

 

[peterhyper]

Won't he require the test gear to complete the minor works cert?

 

[Timmymeads]

Update - I have an electrician to identify the cables tonight - Spent to much time messing about with it - I will look into a online course though as keen to learn from mistakes. I know enough not to electrocute myself... Would this work to test the wires when not live?

Amprobe PK-110 Electrical Test Kit; DMM, Non-Contact Voltage Detector, and Socket Tester from Cole-Parmer United Kingdom

Buy Amprobe PK-110 Electrical Test Kit; DMM, Non-Contact Voltage Detector, and Socket Tester and more from our comprehensive selection of Amprobe PK-110 Electrical Test Kit

www.coleparmer.co.uk

 

[davesparks]

Won't he require the test gear to complete the minor works cert?

View attachment 55575

For replacing a light fitting in his own house? No of course not, that's just ridiculous.

 

[peterhyper]

Do not use a 'volt pen' for testing isolation, they are a rough guide at best and not suitable for testing.

I don't know if that is correct or not as I have not seen your installation and do not know how it is wired, there are many ways to wire a lighting circuit and whilst it is likely that there is one black switched live I cannot guarantee this.

Without a continuity tester and the knowledge to use it it is not possible to identify the cables safely and without making them live.
[automerge]1580892383[/automerge]


That's ridiculously over the top for identifying a few cables to replace an existing light fitting.

For replacing a light fitting in his own house? No of course not, that's just ridiculous.

I get you, so it's only a qualified electrician who has to issue a minor works cert for replacing a light fitting?

 

[davesparks]

I get you, so it's only a qualified electrician who has to issue a minor works cert for replacing a light fitting?

No, nobody has to issue a minor works cert for replacing a light fitting.
Unless there has been a change in the regulations that I've missed.

 

[Pete999]

The problem is that you needed to identify and label each conductor before taking the old light down, failing to do this has left you with a problem.

You need to test each cable to identify its function. Having four cables is unusual, it is normally 3.

What test equipment do you have?

A volt stick probably

 

[telectrix]

a simple continuity tester will suffice. he can lash one up with battery, a bit of scrap cable, and a BULB. ( and long arms to reach the light switch (if he's not already destoyed it))