Lighting circuit dead after repairing fault

[SoSimpleSimon]

I noticed a slight ’electrical’ burning smell in my dining room. I had to hang a shelf for my daughter and thought, I’ll get back to that in a few minutes. While I was hanging the shelf I heard a pop and thought it was a light bulb blowing. When I went downstairs the ground floor lights were all out…, I got a torch, went to the old Wylex fuse box and turned that to OFF. Then I isolated the burning smell to a ceiling light which was fitted with a Lewden Maestro plug-in ceiling rose. I removed the light fitting and saw the melted plastic where the live wires were. Today I removed the fitting and, with the bare wires hanging from the ceiling, replaced the 5amp fuse in the old Wylex fuse box and then turned the electricity back on. All the ground floor lights are still not working…what could the problem be?

 

[davelx]

That light was probably the first in line from the fusebox with loop in/out wiring, so you've disconnected the feed to all the other lights.

We're there three cables entering the fitting? Can you provide a photo?

 

[bernardgreen]

The most likely reason the lights do not work is that the disconnected wires were taking power to the other lamps. They need to be reconnected.

How many cables ( 2 core and Earth ) are there at the fitting.?

If there are 3 then the Lives are Power In. Power Out ( to next lamp ) and power to the switch.

Join these three Lives together, Do NOT join all the Blue ( or Black ) together as one of them is NOT a Neutral but is a Switched Live back from the switch. The Switched Live is the wire that connected to Live in the fitting, Can you identify this wire

 

[terryplumb]

Show us clear pics of wiring present at the ceiling

 

[SoSimpleSimon]

Thank you all… I did wonder if that was the case but I’m simple I hope the pic is clear enough to give you some idea of what’s going on…or not

 

[terryplumb]

You will need to trim back some of those wires to get rid of all damaged insulation .
I can only see 2 red wires is there a third hidden behind the tape ?
You will need to do some testing to establish which those wires are ,particularly which is permant live ,and which is the switch cable.
Do you have any testing instruments ?

 

[SoSimpleSimon]

Thank you Terry, if we call the wires (working anti-clockwise from the live (red) at about 6 o’clock …A, B, C, D, E, F, then, as far as I remember, A & B (both red) we’re connected by a block, C&D (both black were connected by a block, E a black cable with red tape wrapped round it, was in a single block… and the earths were together ….does this make any sense?

 

[bernardgreen]

Ome of the black wires appears to have red tape wrapped round it, If that is the case then that black wire is almost certain to be the Switched Live from the switch.

 

[terryplumb]

Thank you Terry, if we call the wires (working anti-clockwise from the live (red) at about 6 o’clock …A, B, C, D, E, F, then, as far as I remember, A & B (both red) we’re connected by a block, C&D (both black were connected by a block, E a black cable with red tape wrapped round it, was in a single block… and the earths were together ….does this make any sense?

Where is F ? And would it have been connected in a terminal block with the other 2 reds A+B ??
As said above the black wire with red tape would be the switched live ,don't mix that up with the other black wires ,it would connect to the fittings live terminal ,and the other black wires being neutrals connect to the fittings neutral terminal.

 

[SoSimpleSimon]

Hi Terry, the earths are F …. A&B were blocked together, C&D (blacks) were blocked together, E (black with red tape) was separate and The earths F were together…l

 

[terryplumb]

Ok ,please take a closer look at your wiring,there would appear to be a red missing. It could be within the same grey outer sheath cable that the black with red tape on it comes from ,and may be cut off short and not required.

 

[SoSimpleSimon]

Okay, just discovered (with a shock) that there was a “concealed‘ wire…. We now have two cables each with E, N, L and the third with E, N, and the red taped live (from which I just got a small shock) …. It was this red taped wire that I previously thought was a black wire with red tape….the two ‘ordinary’ live wires do not seem to be carrying a charge as I can touch them unharmed ….does this now make sense

 

[terryplumb]

It makes no sense to touch wires to see if they are live !!
Are you now telling us....
1.That there are 3 red wires ( one with red tape).
2. There are 3 black wires.
3. No black wire has red tape on it.
???
You should isolate the circuit that these wires are connected to ,by removing the fuse.
And you need some testing instrument to to prove the circuit is dead ,before stripping all the wires of damaged insulation.

 

[SoSimpleSimon]

Mmmm.... Yes to 1,2, and 3 …the live I got the shock from had lost its casing hence the red tape, I guess.

 

[terryplumb]

Is it your intention to do the necessary work yourself to resolve the issue ?
If it is I think you need someone to talk you through it.