Ceiling Rose - single wire in loop block?

[nosaj87]

I am trying to replace a ceiling rose, but the existing wiring doesn't match my expectation, nor any diagrams I can find to explain it. It is a single pendant controlled by 2 switches. Image of the rose:

https://www.dropbox.com/s/xr5sfeslrt1xehz/IMG_20150224_204329.jpg?dl=0

My current thinking is this must be wired to a junction box with just one of the cables, but then slightly concerning where the broken circuit goes to?

Thanks in advance.

 

[sparkwright]

Firstly, does it actually work?

 

[nosaj87]

Firstly, does it actually work?

Yes, works perfectly (and with both switches)

 

[sparkwright]

Oh. Somehow that makes it harder to put it right!

Out of interest, does the lamp (bulb) seem dim?

I only ask as it's been wired a very strange way.

If it seems bright enough, I would then suggest you send photos of any switches and relevent junction boxes to try to determine how it's been wired and how we can improve it (if it needs it).

 

[securespark]

There's no hidden link between the two blocks holding the blue wires?

 

[Iggifer]

It's all very weird, it all looks like flex to me. The ring crimps are a nice touch though

 

[PrenticeBoyofDerry]

How many individual fittings are operated by the switches?
What wiring do you have at the switches?

My train of thought is maybe more than one fitting, the neutrals and lives have been looped in at another accessory. But a switch live has still required for a second light fitting or possibly an ex-fan.

So the previous installer, used a t&e to do this and parked the spare blue in the ceiling rose live loop.

 

[ericmark]

Clearly centre blue does nothing it is just kept safely out of the way. So we have two switched line and a neutral assuming correct colours. So looking at a standard wiring diagram

then it would seem permanent line has been taken to both switches direct likely by borrowing from next door switch, one single wire between the switches and switched line from both switches direct to ceiling rose.

One wonders why and only thought is some one was trying to get away with using twin and earth instead of triple and earth between switches.

So the top wire shown in diagram has been joined at the ceiling rose.

We do have a problem with our wiring. In the days where we used tungsten bulbs we could ignore the rules for transmission lines although we should always run the line and neutral together we have traditionally run just the line to the switch the miss match caused by such a short run with not a problem with tungsten bulbs. However today using low energy bulbs this miss match can cause the bulbs to light dimmed or flash. This is more of a problem with two way lighting as the line is run separate from neutral for longer. This could be some ones attempt to reduce the effect?

 

[ban-all-sheds]

Clearly centre blue does nothing it is just kept safely out of the way.

A random thought which occurred to me, but I didn't (and haven't) pursued it to see if it holds water was that maybe the centre blue is a N from another circuit - if this is a landing light with the "old-school" way of wiring 2-way hall/landing switches, and then later the up/down circuits are split, a borrowed neutral arises. Maybe a N from the downstairs circuit was run to the rose.

 

[sparkwright]

Ban could be on the right track.

It could be just an un-used core.

I wonder what's behind that ceiling rose?

Maybe the wires we can see are the remains of a previous light fitting, and perhaps there's a joint immediately behind that rose...

 

[eveares]

It's all very weird, it all looks like flex to me.

You can use flex, just not very professional and is usually more expensive than T&E.

There's no hidden link between the two blocks holding the blue wires?

Very much doubt it, although cant tell for sure . The middle blue wire may be a borrowed neutral as BAS said or may just be a old and unused switched live what has not been sleeved brown.

For the two brown wires joined together, may very well be what ericmark said or it could be only one brown wire is carrying current and the other is doing nothing and is terminated somewhere else.

So we have two switched line and a neutral assuming correct colours

I learned that Brown is L1, Grey is L2, and Black is Common.

 

[nosaj87]

Thanks for all the replies. Here are photos of the switches.

Switch #1

Untitled

• nosaj87
• 28 Feb 2015
• 1

Switch #2 (hard to get a shot of - it is the switch closest bottom right with more wires)

Untitled

• nosaj87
• 28 Feb 2015
• 1

Untitled

• nosaj87
• 28 Feb 2015
• 1

edit: that black has a red sleeve too

And the rose again:

Untitled

• nosaj87
• 28 Feb 2015
• 1

 

[sparkwright]

LOOK BEHIND THE CEILING ROSE!!

 

[EFLImpudence]

The switches are wired as would be expected.

However, as you will have noticed, there are no brown/blue cored cables there.

Therefore the switches are either wired from another light or there is a junction box somewhere to which the pictured light is connected.

 

[sparkwright]

Those flexes are 'tinned', the sort often used on light fittings.

My money is on some bodger has removed a fancy light fitting where the main joint is a connector block pushed into the ceiling void, which has been left up there.

SO please LOOK BEHIND THE CEILING ROSE.

If I'm wrong I'll eat my hat.