Replacing tube light with LED. 5 wires..... how to maintain circuit for landing light.

[Cherrypicker9999]

I have a fluorescent light "tube" light in a kitchen that I want to replace with a LED light

There are 5 wires coming out of the ceiling connected to the Live Earth and Neutral on the old tube light batten.

The new LED light I have purchased is plastic so does not need an earth.
I put the Earth wire in a connector and taped it up.

This leaves 4 wires,
1 Red and 3 Black (1980s wiring).

Two combination of black connected to the new LED allow other downstairs light to work, without then in the LED neutral connector they do not work,
I assume they are are both neutral.

I thought the red was permanent live, but it appears to be a switching live. I put that in the LED and it works as do all other downstairs lights,
However, one landing light controlled by 2 switches does not work.

That leaves one black cable. This appears to be a permanent live. If I put it in with the red wire in the LED light the upstairs light works, But switching it on puts the kitchen LED on dim and it will overload. The black live has been taken out and isolated. This seems to indicate it is a permanent live and needs to be connected to supply power to the upstairs light.

If I connect the red and black live together (outside the LED) and move one black neutral to the LED nothing works, If I swap the black neutrals nothing works. This implies both are neutrals and one is not a switching live.

It seems the old fitting had both red and black live connected together. The batten could handle this poor installation and the ballast requirement did not switch it on if the landing light was switched on.

I suspect I need an electrician to connect this black live to a live to complete a circuit to the landing light. This is not a job for me.

My questions:

1. Is my analysis of the wiring correct, or have I done something wrong and there is a simple solution and simple connections?
2. Do I indeed need the black live to be connected to a live for the upstairs light for it to work, by an electrician? Not something I would attempt.
What exactly do I tell an electrician I want doing? Currently the black live is isolated and the landing light does not work.
3. Are there any LED devices that could be used that have a loop or connectors that would resolve my with simple wiring in (I assume a ceiling rose pendant would - but I do not want that).

Any other advice?

Thanks.

 

[endecotp]

The unhelpful answer is, if it was all working before then just connect the new light like the old one was.

Presumably you don’t have a “before” photo. Post a photo of what you have now. Do these wires come from cables that you can see, or are they “singles”?

1. Is my analysis of the wiring correct

I doubt it.

, or have I done something wrong and there is a simple solution and simple connections?

More likely.

What exactly do I tell an electrician I want doing?

“Make my lights work”.

3. Are there any LED devices that could be used that have a loop or connectors that would resolve my with simple wiring in (I assume a ceiling rose pendant would - but I do not want that).

If you need a “loop” connection, just join the wires with a terminal block or wago connector.

 

[Cherrypicker9999]

The wires come from the cable you can see in the photo.

Effectively, where do I put the black live?

In the previous batten it seemed to be in with the red live.
As, I stated I cannot put 2 lives in the live connector of the LED. It completes the circuit, but in time overloads and all lights go out.
It also means when the landing light is switched on the LED kitchen light is on dim. This was not an issue as the kitchen light would not come on as the ballast was needed and the batten seemed to be able to cope with a permanent and switched live. An LED cannot.

An electrician did it years ago and did not label the wires.

 

[endecotp]

All singles - interesting!

in time overloads and all lights go out.
It also means when the landing light is switched on the LED kitchen light is on dim. This was not an issue as the kitchen light would not come on as the ballast was needed and the batten seemed to be able to cope with a permanent and switched live. An LED cannot.

It’s probably best if you just describe the symptoms that you actually see, rather than expressing conclusions!

A dim light might mean that you have connected lamps in series.

Excuse me if I’ve missed this, but what happens if you put the red wire in the new lamp’s Live terminal and all three blacks in its Neutral?

An electrician did it years ago and did not label the wires.

They never do.

 

[Cherrypicker9999]

1. Two specific black wires in neutral needed for other downstairs lights to work.

2. Red wire in live with those 2 black all downstairs lights work correctly. Upstairs landing light will not work.

3. Red wire in live and other black wire in live plus two same black still in neutral, all lights work including landing. But if one switches landing light on it causes kitchen LED to come on dim and after some time all lights go off. (Hence, as you say connected in series and can that conclude that black cannot be neutral, it is a live?).

4. All three black in neutral - nothing worked.

 

[endecotp]

3. …. after some time all lights go off.

4. All three black in neutral - nothing worked.

In these cases, did it trip the MCB / RCBO / blow a fuse in the consumer unit that you had to reset?

 

[endecotp]

It would seem that some of the wires go to other downstairs lights and the landing light.

If I were you, I’d try to identify which two wires you need to connect to this new light so that it alone works - with the two other wires not connected to anything, and the other lights not working at all - and nothing going dim or going off after a while.

Oh, and…

1. Don’t electrocute yourself. Is there someone around who will notice if you get zapped? Turn the power off.
2. Do you have a multimeter?

 

[Cherrypicker9999]

In these cases, did it trip the MCB / RCBO / blow a fuse in the consumer unit that you had to reset?

No it did not trip. Just nothing worked.

 

[Cherrypicker9999]

It would seem that some of the wires go to other downstairs lights and the landing light.

If I were you, I’d try to identify which two wires you need to connect to this new light so that it alone works - with the two other wires not connected to anything, and the other lights not working at all - and nothing going dim or going off after a while.

Oh, and…

1. Don’t electrocute yourself. Is there someone around who will notice if you get zapped? Turn the power off.
2. Do you have a multimeter?

No multimeter. May be time for an electrician!

 

[Cherrypicker9999]

Currently I have red in live.
2 blacks in neutral.
All downstairs lights work.
Just upstairs landing does not as the last black is not connected.

 

[endecotp]

Currently I have red in live.
2 blacks in neutral.
All downstairs lights work.

Remove one or other black wire, so you know which of them goes to the other downstairs lights.

You should then be able to label the wires as:

- Incoming neutral
- Neutral out to other downstairs lights
- Switched live
- Mystery wire somehow related to landing lights.


Edit: you might also experiment with all four permutations of positions for the two switches for the landing lights.