Ceiling light question...loop system

[plodius]

Hi guys, I have a really daft question . First a bit of history....4 months ago paid a registered sparky 150 quid to install some ceiling fans with lights in place of the standard pendant lights that were there. To cut a long story short, had to get a second sparky out to fix the job he had buggered up( he failed to wire two lights completely and asked me to pay for his driveshaft which allegedly had snapped on his way back to check the job some six weeks later). We are now moving and I have replaced all the lights with the original or new ceiling pendant lights, it was a bit of a nightmare because he didn't mark any of the switched live wires, there were connector blocks everywhere...
All the rest of the house is fine, apart from one of the two lounge lights. The first light has three cables to the rose, consisting of 3 black, 3 red and 3 earth wires, the switch that controls that light works fine as do all the other downstairs lights on the same loop. All apart from these last two which appear to be connected to a dimmer switch(never used it because we had ceiling fans and they don't like being tweaked by a dimmer).
The last light has only one single cable from the ceiling, consisting of one each of red. black and earth cables. I tried the conventional LNE configuration on this last light but the result was it worked via the second conventional switch but was permanently on. That is the dilemna, as there is only this one cable consisting of 3 wires, how does that figure in to the loop? I should add that the other lounge light with the 3 cables is also able to be switched by the dimmer switch, both on and off...My brain is scrambled....

 

[EFLImpudence]

Sorry about your 'electrician' - we're not all like that.

The last light has only one single cable from the ceiling, consisting of one each of red. black and earth cables. I tried the conventional LNE configuration on this last light but the result was it worked via the second conventional switch but was permanently on.

This will be correct. The fault will be elsewhere.

That is the dilemna, as there is only this one cable consisting of 3 wires, how does that figure in to the loop?

It will be the last one at the end of the line. Because there is only one cable it will be form one of the other lights and will work simultaneously.

I should add that the other lounge light with the 3 cables is also able to be switched by the dimmer switch, both on and off...My brain is scrambled....

Likely one cable will be power, one will go to the switch and one to the other light, above.

Do you have a meter so that you can determine which cable is which?

 

[EFLImpudence]

Have just reread. If the light with the three cables is working properly then -

Are all the red wires connected together at this light? They shouldn't be.

 

[sparkwright]

So you have two lights in the lounge controlled by one switch?

The fault will lie in the first fitting, which has lots of wires.

You need to find the red wire here which goes to the second light.
At the moment all the reds will be in a connector block of their own (known as the permanent live or loop).

This one particular red needs removing, and will go together with the single black wire (known as the switched live). The black should be sleeved with a piece of red sleeving to indicate it is live and not neutral.

Make sure the power is OFF before starting work.

 

[plodius]

Well sods law was obviously having a bank holiday today, as the first red I switched to go with the switched live was the feed to the other light with just the one 3 wire cable. Both lights now operate by the wall switch and the dimmer switch, and lol I should hasten to add, all the other downstairs lights operate correctly and no tripped breakers either.

Just goes to show that pro's are pro's whether they are in your house or not, and cowboys that pretend to be pro's should stay at home, preferably their own......

Once again thankyou........