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[Myrtle]

I have not yet managed to solve my wiring issue and wondered if anyone can help. I am replacing my dining room light fitting. I have 3 cables coming out of the ceiling. One goes to the light switch; one goes to the living room light and the third is the loop. Both the cable that goes to the switch and the one that goes to the lounge light have 4 wires. Red, blue, yellow/green and a separate yellow. The switch has just one cable to it but it operates both the lounge and dining room lights. The separate yellow wire goes to L2 in the top row of the switch, the red goes to L1 in the top row with a second red going from L1 on the top to L1 on the bottom. The blue goes to L3 on the bottom.
I cannot work out how to connect the two yellow wires, with the brown light fitting wire. I assume that they need to be connected together but then where does the brown go? When I had the two yellows into one half of a connection and the brown into the other side, neither of the 2 switches on the light switch operated either the lounge or dining room lights BUT I did find out that the kitchen light switch operated all the lights but on very much reduced power. I know that's not right!!! I did draw a lovely picture to show you but I don't know how to insert it to these message boards. :? [/img]

[ericmark]

Although this forum does not allow photos others do. But your house does not follow standard wiring and as a result you are unlikely to get anyone who can tell you what to do.
What it seems is instead of using a separate cable from the switch to each lamp there is a three core cable between lamps and from lamps to switch. There is nothing wrong with doing this it just means very careful notes need taking before disconnecting anything.
Switches sometimes have a Com and L1 plus maybe L2 and others are marked L1 (which = Com) and L2 plus L3 I will guess to have latter. But with a single way switch the L3 terminal would not normally be used.
The only way I could work it out once cables have been mixed up would be to ring out all the cables and mark them all up.
I think that is only way. I can give you diagrams on how standard wiring is done but not how non standard wiring is done you must look on the wiring diagram that the builders left or failing that ring every wire out.
Eric

[ericmark]

Try http://www.ericmark.talktalk.net/lights.htm does this help?
Eric

[Myrtle]

Thanks ericmark. I'm not sure what 'ring out' means but I can make an educated guess and therefore probably needs the help of someone qualified. There are no instructions to my house - it has been knocked about over the years and needs many jobs doing so the wiring is just one of the non-standard features! I have since had to go into the loft acess in my kitchen and found some more creative wiring in there so it all probably needs looking at and sorting out. Thanks for your help.

[ericmark]

Many years ago one would use an electric bell and batteries to test continuity although today we use a multimeter set on ohms normally with built in buzzer we still call the process belling out.
Only you know how good you are. And only you can work out when you need to call someone else in.
I did make up detailed instructions on how to work out which wire was which using the light itself but so many people got in a knot trying to follow it I have given up posting that now.
I will if you want but it seems only electricians seem to be able to follow logic!
Eric

[Myrtle]

Thanks for the explanation. I have tested with a meter and had already discovered that the two yellows that I have are the 'switched' cables but only one of them is connected to the switch itself and the other one is the feed to the next lamp. [i]Although[/i] I did disconnect the old ceiling rose before checking what went where, I was sure that the two yellows were just connected together in a separate terminal connector. I cannot for the life of me remember where the flex live was connected to though as I'm pretty sure it wasn't connected to the yellows and that doesn't seem to fit with what should normally happen. I can follow step by step instructions and indeed I fitted the lounge light fine as that was all as it was meant to be, but I think you'll agree, I don't think the dining room wiring in my house is 'traditional'. There is another base plate from a ceiling rose being used as a junction box in the loft space of my kithen which, I discovered, is in turn connected to, what I believe will be a terminal connector block, that is wrapped all over in insulation tape. I discovered this when putting a bucket in the loft to collect the water from the leak in the roof which also needs fixing! When I saw the extra creative wiring I thought I would probably give up at that point and have someone professional to check it all to be on the safe side! :)