Ceiling rose comes on dimly when other lights switched on!

[Spaceaceuk]

Hi there,
I recently fitted a new ceiling rose. When I took the old one off I took pictures of the wiring as it didn't look to be done in a standard fashion but the old light had worked so thought I would wire the new one up the same.

Untitled

• Spaceaceuk
• 11 Nov 2013
• 1

Untitled

• Spaceaceuk
• 11 Nov 2013
• 1

When I did this the light just didn't come on no fuses blown.

So I went back to the diagram with the new ceiling rose wired it up as shown and blew a fuse so I figured I got the switched live wrong. Re fused and re wired and the light now works and dims perfectly only problem is that when it is off and I switch other lights on on the upstairs loop it comes on in varying degrees of brightness and when other lights are on and I switch this one on it dims the other lights.

I also noticed today when trial in another bulb that when no bulb is in the socket no other lights come on on the loop.

Please could somebody advise. I thought I may have got the switched live wrong again but I checked with a multimeter for continuity and It was correctly wired.

Hope someone can help I don't want to have to admit defeat and call the father in law in lol

Cheers

Joe

 

[ban-all-sheds]

The only thing wrong with the way you found it was that the actual light flex was the wrong way round - brown should have gone to the switched live (the black on its own) and blue to the neutral loop (the two blacks together).

The reason the light didn't work when you first changed it had nothing to do with the flex being the wrong way round - everything else was correctly connected, and quite obviously so. So when you "went back to the diagram with the new ceiling rose wired it up as shown", all you needed to change was the polarity of the pendant cable.

But you changed the way the fixed wiring was arranged, first by deciding to put the switched live in with the neutral (because you didn't understand how what you were fiddling with worked), and now you've managed to get the light in series with the loop.

You know which is the switch drop cable - just put everything back the way it should be.

 

[Spaceaceuk]

Just checking with reference to what you saying both those pictures are how I found it. I was under the impression the lives went into the loop block. When I found them they were in the neutral block.

 

[securespark]

You've got something muxed ip.

First, you need to safely isolate.

You then need to go back to square one and identify the cable pairs.
Then, you need to ID the switch drop. Do this with the continuity setting of a DMM.

Once you've done this, with the DMM, you need to ID the incoming supply: having put connector blocks on each wire, reconnect the supply and check for 230V between L & N and L & E.

The remaining cable (if your photo's show the wiring connected up accurately) should be the outgoing supply.

The reds go together, the two blacks from the incoming and outgoing supply cables go together for the neutral and the other black (marked with red tape) is the live return from the switch.

 

[ban-all-sheds]

Just checking with reference to what you saying both those pictures are how I found it.

Yes, I know, and it was all working when you found it.

I was under the impression the lives went into the loop block. When I found them they were in the neutral block.

Wires can't read the writing on ceiling roses. Electrically what you had was correctly connected. Using the "right" terminals might make it easier to hook the pendant flex over the strain reliefs, but that's all. When you replaced the rose, why did you neither replicate what had been there before nor put all the lives in Loop and all the neutrals in Neutral?

 

[Spaceaceuk]

As I mentioned previously I notes the wires wired it up exactly the same as was before and nothing happened.

As for wires not being able to read I don't know that you can put them in whatever block you wan that's why I'm on here asking for advice.

 

[ban-all-sheds]

As I mentioned previously I notes the wires wired it up exactly the same as was before and nothing happened.

The reason the light didn't work when you first changed it had nothing to do with the flex being the wrong way round, or the lighting loop using the "wrong" terminals in the rose.

As it does still light up, it's unlikely to have been a broken flex, or a problem at the lampholder, or a blown bulb. Could have been that you put one of the conductors in too far and weren't making contact with the copper.

As for wires not being able to read I don't know that you can put them in whatever block you wan

You can see that they're just small, isolated pieces of brass?

Anyway - is it working now?

 

[Spaceaceuk]

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• Spaceaceuk
• 11 Nov 2013
• 1

This is how it looks currently with the whole dimming situation going on

So are you suggesting I swap the brown and blue wire??

 

[ban-all-sheds]

No - I'm suggesting you wire the actual rose itself the way it's supposed to be wired.

You know which is the switch drop cable - just put everything back the way it should be.

 

[Spaceaceuk]

Which is?

Correct switch live is with brown what else is wrong?

 

[sparkwright]

You have two blacks the wrong way round.

Find the black that goes to the switch. This black goes on it's own, with the brown flex.

The remaining two blacks go with the blue flex.

Keep reds together in the centre block.

Sleeve earths with green and yellow sleeving and connect to the earth terminal.

 

[ban-all-sheds]

Correct switch live is with brown

Sure about that?

 

[Spaceaceuk]

Yeah as I said I isolated the supply at the fuse box then did continuity with ohms / bleeper and got it from the one that change when the switch was operated.

 

[sparkwright]

If you have correctly identified the switch cable, and you have problems, I can only conclude there's a fault somewhere else, OR it's supposed to be wired in an unconventional way - this can occur, usually when alterations have taken place, though it's rare and impossible to guess.

First things first - is it just one switch and one light in this particular room?

EDIT - when you did your test on the switch wire, were all the wires at the light disconnected?

You test (with the power off) for continuity between the red and black of each cable - flicking the light switch on and off and checking for continuity.

 

[Spaceaceuk]

Yeah that's correct connected to a push button 2 way dimmer switch connected to just c and l1