Totally baffled on lighting problems !

Mr Zogs · Nov 5, 2014

Hi I'm new here and an apprentice at the moment so forgive me if I've posted in the wrong place ! Sorry.
I have just been doing wiring bays at college reference one way lighting, 2 way, 2 way intermediate etc and all with feeds and Neutrals looped through the switch boxes at the wall. I have also looked at older junction box wiring a little but am not that clear on all that stuff as I've found a couple of really messy un-identified cable ones in a loft recently.

What I wanted to ask is if you can legally and safely have say a centre light in a bedroom for example fed one way via one switch of a 2 gang plate and also have that same light fitting switched from another gang on same plate which also switches on 2 bedside downlights 2 way. So all 3 lights come on together, but centre light can also be switched on alone ? and then to make things more complicated the bedside lights can be switched on and off with switches for each one next to bed side also and work 2 way !! At college we are only wiring one switch wire to each light and looping the switched line across to a 2nd light if say 2 are to come on together etc... Never seen anything like 2 ways of switched feeds to light fittings like this and cables everywhere... Please help...

telectrix · Nov 6, 2014

some weird ways are devised for light switching when customer wants this, that and that. as long as regs are complied with, it's just a case of getting your head round what has been done.

Guest111 · Nov 6, 2014

One tip for you,lose the term "legally" the wiring regs are not a statutory instrument and therefore not enforceable by law,while compliance with the regs MAY help your defence in a court case nobody has ever ended up in court for failing to comply with them,yes people have been prosecuted as a result of incidents arising from non compliance but not solely from failing to comply.e.g you will not be locked up for not fitting an RCD where the regs state you should,however you may be locked up if someone got hurt as a result of this.People using the term legally in the wrong context can end up looking rather silly,so there's a tip for you as an apprentice,btw this isn't meant as a dig.

Richard Burns · Nov 6, 2014

If you have lighting that can be simultaneously switched, whether two way or one way then it is not possible to get the lights to operate individually in standard wiring because the switch line must go to all lights and so any light on would turn all lights on.
However the use of relays can permit the sort of arrangement you describe, though I would say this is most unusual in domestic.
The more common "odd" arrangement in domestic is a set of lights that can be switched centrally and then each light has an individual local switch that can turn the light off, however then when switching centrally this light would remain off.