Help with lighting

[oh dear]

I have just installed 2 light fittings where previously there were spot lights connected in series from 1 switch.

The problem is that as soon as the power is switched back on both lights are on, even when the switch is off, although a lot dimmer than when the switch is on. When either bulb is removed the other does not light.

I have checked the switch cables using a meter so I know they cannot be the problem, and have checked and double checked the rose is connected properly (as per instructions).

Please help it is a Sunday and I have had enough!!

 

[Steve]

the original fittings were in series? you sure? parallel more likely, though i suspect that somehow you have them in series when the switch is off. I have drawn a diagram on paper to try and figure it out but i cant for the life of me work it out! I would like to know the answer if anyone else knows!!! My brain hurts!

Did you not note what went where in the old fittings? this is the key to everything.

 

[geezer]

hi there


tricky one, have you disconected the transformers or maybe the one transformer of the spotlights?

 

[oh dear]

Unfortunately I didn't note what went where in my keeness to get on with the job, but have sorted the switch wires, and tried the others in each combination possible.

I have just noticed transformers on the spots I removed. Unfortunately I have no idea what difference this would make - can you explain please?

Thanks

 

[Steve]

the second light should be connected the same way as the first - to the same terminals, Switched Live and neutral.

switch goes between Live and Switched live.

Lights shouldn't be connected to live at all. just switched live.

Hope this helps.

Nothing to worry about with transformers - unless your new fittings have transformers and you've connected mains to the secondary side

 

[geezer]

I have just noticed transformers on the spots I removed. Unfortunately I have no idea what difference this would make - can you explain please?

Thanks

Well if the transformer from the spots were left on in the circuit, which they are not, thats one reason why the lights would be dim but i believe crafty has the rest of your answer its in the connection like he said.

 

[DarrenSL]

I'm no expert but ... sounds like the lights are connected in series to me and in such a way that they're permanently live. Then, when the switch is flipped, the circuit somehow becomes parallel and hence bright.

I can't easily work how this is achieved but if I were you I would disconnect all the red wires and find the live. This would be the ring main. Connect this to the Live on your rose then connect another of the red wires to the live block on the rose. If all the lights in the house are working then you've found the other ring live. If not, check the switch. Is it live? If so you've found the switch live, if not you've found the live which goes to your second light fitting. Finally connect the light fittings but remember (as Crafty has said) light fittings go to the switch live not the circuit live.

I may have over simplified things a bit but if you follow the logic you should be ok.

 

[ban-all-sheds]

disconnect all the red wires and find the live. This would be the ring main.

Ring main????????????????????????????????????????????????????

 

[DarrenSL]

Ok, enlighten me please What's the correct terminology for the live (ring) of the lighting circuit? I did say I'm no expert.

 

[Qedelec]

Darren, lighting circuits are rarely connected as a ring. they are connected as a radial.
Advice on this forum is usually informed, as it is subscribed to by many time served sparkies.
If in doubt, why not hold back before posting. The answer given by one of the old timers will often add to you education.
No offence intended.

 

[johnny_t]

Brain not working properly at the moment, so I can't think this out fully, but I have seen something like this happen when the (I think) Switched Live is mistakenly connected to the neutral return from further on in the circuit. If you turn off all other lights in the house is this one still on dim when in the off position (and I promise I'll try and think it out a bit better when I'm less busy)

EDIT: Brain warming up a bit. If you have the wrong two black wires connected together (Switch live and Neutral 'Return') instead of Neutral Feed and Neutral Return (my terminology, but I hope you know what I mean) then when any other light further in the circuit is on, you will always have a reduced voltage at the switched live terminal in your light. When you turn your switch on, you get the full voltage at that light and the lights further in the circuit will go off. There is maybe only one further in the circuit and you haven't noticed this part of the phenomenon yet.

 

[Adam_151]

Lighting rings are usally installed by plumbers who think they can do electrics

 

[Qedelec]

Lighting rings are usally installed by plumbers who think they can do electrics

And are registered Domestic Installers so know from the 2 day course all all about electricery