1-Way Dimmer controlling 2 lights, Help!!!

[N0D0ughDaz]

Hi All,

I am hoping some of you experts can help please???

I had a single switch which controlled two separate lights (2 individual flex's coming from separate parts of the celling both with an energy saving light bulb on each)

We decided it was time to become a bit posher and change these for matching light units with three bulbs on each unit. This would cause a problem that the light would be too intense with an either ON or OFF selection, so I decided to get a dimmer switch. (so a single dimmer switch controlling both light units)

I assumed this would be a straight forward process by changing everything like for like (wiring wise) and I'm pretty confident I done this.
Once it was wired up, I switched the fuse box back on and 1 of the light units was constantly on and had no effect or worked in any relation to the light switch. The other light unit worked correctly to the switch (Push in and out, it came on and off and dimmed correctly.) But the other one stayed on constantly!!!!
(I am using 3 off 24w non energy saving light bulbs on each unit)

I thought "I know what I've done! I have got the Live and Neutral the wrong way around" I check and it seemed correct but I changed it around to make sure. This had no effect whatsoever, it still stayed on constantly.

Is there any sparky out there that knows exactly what balls up I have made or is this a dimmer switch thing?

Thanks for your help in advance!!

Still No Dough Daz!!

 

[1stassetelectrical]

Hi sounds like the fitting that is on constantly is being powered by the permanent live rather than the switched live.
search using google (other search engines are available) for loop in light wiring diagram should be able to see where you have gone wrong with that.
Paul

 

[tonyelectric]

Right, here we go..

I'm assuming by non energy saving lamps at 24W you are referring to G9 capsules running at 230V and not low voltage lamps that could be a whole other ball park.

In the switch you will have either a live feed coming into the dimmer at the terminal L1 or Com and a switched live going up to the lights.

or

There will be lives and neutrals in the switch box meaning you have the loop in done at the switch.

in order to advise we need to know all the details, pictures help

 

[echoes]

Have you got two 2-core cables at this switch, and do all the conductors connect to the switch terminals?

If so, each cable will use one conductor for live, and the other for switched live. They should be red/brown or sleeved red/brown. There will be no neutrals connected to the switch itself.

It sounds like you have got the conductors for the light which doesn't switch off connected the wrong way round - i.e. you have connected the switched live for the light directly to the permanent live feed.

EDIT: b**g*r: too slow...

 

[N0D0ughDaz]

Thanks Guys,

1stassetelectrical,

The light that is constantly on only has a single Live, a single neutral and a single earth and I have already changed them around thinking I screwed up first time but on both occasions the light was constantly on with no relation to the switch, it's as if it's live feed is separate (but why would it work when originally???)

tonyelectric,

The bulbs are 25W, 240v, E14 bulbs (filament bulbs, non of this energy saving lark, as I know they don't work on dimmers)

I replaced like for like in the switch - Red in the L1 and the other in the common (nothing in L2)

echoes,

no 2 core cables in the switch. The switch was a straight forward change over. Two separate cables (L1 & Common) I even done it wire by wire so I didn't confuse myself (which is easily done).

That's what I originally thought about the live & neutral the wrong way around so I swapped them, but it still was on constantly.

 

[N0D0ughDaz]

........ I forgot to mention that I only had a wire each from the light that was constantly on (x1 live, x1 Neutral, x1 Earth)

The light that worked correctly to the dimmer switch had x3 Neutral wires that I bunched together in the neutral terminal....

x4 Live wires, I bunched x3 together (as part of the loom) and used the other one for the Live terminal for the light unit.

x3 earth's which I bunched together into the earth terminal. But I assume because this is working OK then it is correct, unless I am missing something that isn't as obvious as that???

I would like to send pictures but one unit took me about 45 minutes to fit all the wires in and secure to the celling. I think I will end up throwing it through the window if I have to do that again!!!

 

[N0D0ughDaz]

.....Right, I think I may of worked out what I have done wrong, so I'll run it past you lot to see it this is how it could be wired up in a house???

I'm thinking that the light unit with the multiple neutral & live wires, one of each of the wires Tee off to the other light unit, instead of having wires that are part of the loom?

What I may have done is the Live wire that tee off to the other unit I have muddled up and put in the loom and used another for that unit. So if that live that tees off to the other light unit is in the loom it will be constantly live.

...but thinking about it, aren't all the lives constantly live anyway???

I'm confused!!!!

 

[echoes]

Things may be becoming clearer...

... so you have 2 ceiling roses, and from one of them there is a switch drop?

Sounds like the second light (the one with just L, N and E) should be connected to the switched line & neutral of the first light, and NOT the unswitched line. That would explain it.

 

[N0D0ughDaz]

echoes,

Thanks for your efforts, it's much appreciated.

So, does this mean I am thinking what you're thinking???

Should I change the live wires around (from the loom to the light unit) until I get it working?

the more I think about it there may of been 2 live wires feeding the light unit. Could this be one of the 2 wires linking from the first light unit (the one with multiple live's and neutrals) directly to the second unit.
But again, it comes back to the fact that the lives are constantly on anyway, so does it make any odds??

 

[riveralt]

Just to clarify: You originally had two pendant lights with ceiling roses both operated by a single gang switch?

Your, new fancy lights, are replacing the pendant lights AND ceiling roses?

If the answer to both is yes then...

From what you have said so far, one of the ceiling roses (the one with line loop, neutral loop and earth loop) is your main unit - it should be controlled by the switch. The second ceiling rose (the one with only line, neutral and earth wire) is switched from the main unit.

What type of wiring arrangement is in the new lights - if it is replacing the ceiling rose then it will probably have a L, Earth, Neutral and blank terminal.

If this is so then....(you might need a multi-meter)
Start at the switch....

Firstly - what colour and how many wires do you have at the light switch?
You should only have three - normally one red or brown, one black or blue and one earth. The red/brown one goes in Common and the black/blue goes in L1. Some dimmers do not have C and only have L1,L2 and L3 - in which case red = L1 and black = L2.

Once these have been established - the black/blue wire is your switched live. You need to id this at the ceiling rose. You will also need to id which wire links to the secondary light. ID them and mark them so you remember.

Once you have done that the switched live wire at the ceiling rose goes into the L on the main unit. Together with the red/brown wire from the secondary unit.

The other group of black.blue wires go together into the N and the earths go into the earth. The red wires go into the blank terminal block (if one is not provided then you will have to put them in a single block yourself and wrap with tape.

At the secondary light... The red wire goes into L, the black wire goes into N and earth goes into earth.

It should then work - though check that your dimmer is the right value.

 

[1stassetelectrical]

the wiring problem is in the loop of the light that works ok, you have connected the live to the perm on light to the supply side instead of the switched side. if you can identify the wires going to the one thats perm on there the red or brown depending how old cable is needs connecting to the opposit red/brown (should be sleaved to identify as switched live but prob not lol) which is the switch wire connection.
Hope this helps
and be carefull
Paul