Help with ceiling light issue

[mastin]

Hi, I had a lok in the sticky about diagrams above but because it was so old. The majority of them are no longer found.

Essentially I am in a bit of a bind. My aunt bought a new pendant light for which my uncle put it up. Light in the living room did not work but all the others did. I was up visiting & they currently have their grand-kid staying for a few days. So upon seeing the light, idiot here offered to 'fix' it as I'm familiar with newer wiring but they have the old red & black. I opened it up, took down the pendant put a larger terminal block on it. Put it back up & now not a single light in the house works. Which given there is a small kid in the home. It's made me feel like a right halfwit so am going back up tomorrow to get something sorted. I have posted the pic below & hope someone can please tell me where I am going wrong here & can point out the right way round.

There are two flexes. Each one with a single black, red & a bit of copper without sheath. One of the red wires has a slight nick in it exposing a bit of copper so I put a bit of blue electrical tape over it as that was al my uncle had laying around. There is no other single cable that would be the switched live there at all.

Can someone please tell me the correct order so I can get this sorted. I can increase the terminal block size if needed. Many Thanks, James..

Ps. I have truly learned my lesson on this & from now on will be keeping my gob shut on matters which I have no right to be meddling in.

 

[EFLImpudence]

If wired in the usual manner, you will have blown a fuse or tripped an MCB.

Do you have a multimeter?

Normally the two reds are connected together but to nothing else in one terminal.
One of the blacks will be Neutral connected to N on the lamp and
one will be switched live connected to L on the lamp.
Which is which is not possible to tell from here. You will need a meter to test.

WITH THE POWER OFF and wires disconnected - test.
The black with continuity with its red (in the same sheath) when the light switch is on will be the switched live.

If you have long enough wires, cut back to the nick.

The CPCs(earths should be sleeved green and yellow and connected together as you have done.

 

[PrenticeBoyofDerry]

As ELFI has kindly explained. the set up you have is common to a loop-in connection. Which would suggest that one of the blacks does not belong in the neutral terminal but actually is the switch live and terminate at the live side of the fitting. Therefore the two reds would create the loop back to the switch and do not get terminated at the live side of the light, but are terminate in a separate terminal block (you require an extra/spare block for this), and if you can strip back the red insulation back to the nick in it, it would be wise, if it cannot be cut back due to length, then it can be heat shrunk or re-jointed.
By putting blue mark up on this, it could cause confusion for the next person at the fitting and electrical tape is not a insulator!

The CPC (aka earth should be sleeved green/yellow)

But for you undertake the above tasks safely you do require some electrical test equipment to prove what you are doing is correct and safe.
You need to determine which conductors are live and which one is neutral and that you have continuity and polarity.
This can be done by continuity test, then voltage test using a two pole/probe multi meter.

The one thing that cannot be taken for granted, is that the core colours have been wired as normal or standard, so always test, if you have taken apart without noting down positions of conductors, or at least taking some photographic evidence of the fitting and conductors positions prior to dismantling.
NB: School Boy Error, go sit in the corner

 

[ericmark]

I think it should look more like this. One of those black wires should have a red sleeve which has either fallen off or never been fitted. Plus of course sleeving on the earth wires.

 

[bernardgreen]

Eric, that is a brilliant bit of photo editing. ( or did you nip round to the OP, move the black wire and take a photo )

 

[PrenticeBoyofDerry]

Eric, that is a brilliant bit of photo editing. ( or did you nip round to the OP, move the black wire and take a photo )

I hope he tested for switch live first, shame he did not sleeve it though!

 

[mastin]

Thanks for the help guys. Unfortunately it was to no avail. Tried the suggestions (without a multimeter as I tossed my clamp multimeter a few months back after losing the battery compartment).

I tried a few different permutations and not a single flicker of light from anywhere. Thankfully sockets etc are all still working so brought up some lamps. The little one is pulling in the neighbours to tell them I broke her light.

My first thought was that it was a fuse being old wiring so went out and bought some fuse wire just in case. However there is none of the old ones there. So have bitten the bullet and called out an electrician who is supposed to be coming tomorrow afternoon. Will let you know what it turns out to be.

Ps. Ericmarc - That is some good PS. Had it not been for the slight blur on the end I would have thought that to be real.

 

[sparkwright]

The way you originally wired that light would have blown a fuse or tripped a breaker.

Check all RELEVENT switches, trips, RCDs whatever the case may be are in the on position.

Some 'trip switches' (I don't want to get too technical) need pushing down before pushing up.

And you shouldn't have any exposed copper wire showing, as this could cause a short if it touches something else.

 

[Taylortwocities]

I'm interested to find out why there is a bit of blue tape on a red conductor. Maybe it is trying to tell us something!

Will edit for the outcome.

 

[bernardgreen]

When you joined the two red and the two blacks it would have put the switch between Live and Neutral. Turning the switch ON would have put a dead short between Live and Neutral. This would ( should ) have blown the fuse or tripped the MCB which ever is in your fuse box. It would also have damaged the switch.

If it is only this light that is not working then the switch has been damaged and it cannot close the circuit to put power to the lamp.

If other lamps are no longer working then check the fuse box. If you have MCBs then the one for the lighting may have tripped. Some MCBs have to be turned fully OFF ( push lever right down ) before they can be reset by pushing the lever right up. Just pushing the lever up does not reset the MCB

If no fuse blew or MCB tripped then the short circuit may have damaged a connection elsewhere on the lighting circuit.

 

[EFLImpudence]

I'm interested to find out why there is a bit of blue tape on a red conductor.

OP said there is a nick in the insulation and he covered it.

 

[ban-all-sheds]

Had it not been for the slight blur on the end I would have thought that to be real.

It is real - he cut the strip with a hot knife.

 

[mastin]

The way you originally wired that light would have blown a fuse or tripped a breaker.

Check all RELEVENT switches, trips, RCDs whatever the case may be are in the on position.

Some 'trip switches' (I don't want to get too technical) need pushing down before pushing up.

And you shouldn't have any exposed copper wire showing, as this could cause a short if it touches something else.

It did trip a single breaker the moment I switched it on. The box has a main switch and 4/5 other circuit breaker switches that are all unmarked and another red one at the very end. Beside that is the power meter and a few grey boxes with cables marked N, L etc which all have the little wire cable tieocks. There is no other fuse boxes or anything as I was initialy expecting (even bought some fuse wire before going back round in anticipation) but my aunt assured me that was all there was.

I did switch all off and on a couple of times yesterday in between changes on the terminal block. I also done it straight after the initial trip. Although not immediately after I tried ericmark's suggestion. I flipped them all on and off after trying the separate terminal block loop idea from PrenticeBoyOfDerry.

The exposed copper on the earth wires is in every single room. Not one trace of green/yellow anywhere. The other bedrooms all have 3 flexes connected up to the rose. Switch live, loop etc are all marked on the plastic. The living room light I took down never had that as the previous owner had changed it to a more modern light. Which my uncle had taken down and attempted to put up a new one. After his change, the living room light did not work but all the others in the home did. Hence why I didn't bother to take a reference pic before starting.

 

[mastin]

When you joined the two red and the two blacks it would have put the switch between Live and Neutral. Turning the switch ON would have put a dead short between Live and Neutral. This would ( should ) have blown the fuse or tripped the MCB which ever is in your fuse box. It would also have damaged the switch.

If it is only this light that is not working then the switch has been damaged and it cannot close the circuit to put power to the lamp.

If other lamps are no longer working then check the fuse box. If you have MCBs then the one for the lighting may have tripped. Some MCBs have to be turned fully OFF ( push lever right down ) before they can be reset by pushing the lever right up. Just pushing the lever up does not reset the MCB

If no fuse blew or MCB tripped then the short circuit may have damaged a connection elsewhere on the lighting circuit.

It did trip a single breaker the moment I switched it on initially. None of the lights in the house are working now. I have tried turning everything off and on a couple of times yesterday. As well as the night before. In my attempts yesterday, there was not a single trip.

There is no fuse box. Just the main box with a main off/on red swutch. 4/5 or so unmarked black.circuit breakers and another red swutch at the end. A few grey boxes with N, L with wire ties and the end one has a power company property sticker. The only other thing is the power meter. There are no other fuse boxes etc anywhere.

 

[securespark]

Need a picture of what you say tripped.

It might be damaged so that even in the on position it is not allowing electricity through to the circuit.