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Do I wire a single wire from a dimmer switch on the wall to the red live or black neutral wire up on the ceiling light fitment

Postby dreamwhizzy » Sat Dec 14, 2019 3:56 pm

Do I wire a single wire from a dimmer switch on the wall to the red live or black neutral wire up on the ceiling light fitment
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Postby Mr White » Sat Dec 14, 2019 11:01 pm

Could you expand on what you are trying to achieve and what you actually have.
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Postby ericmark » Sun Dec 15, 2019 1:07 pm

1) With lights wire colours do not tell you what they do, very common to have a black wire which is line not neutral.
2) There are two types of electronic switches, those which require a neutral to work, and those which use the current through bulb to work, the latter have to have dimmer-able bulbs fitted or the bulbs will flash.
3) Two way switching with electronic switches often does not have mains voltage on the third wire, and has to have a special slave switch as second or more switches on the circuit not a standard two way switch.
4) Early two way switching would borrow a line from another switch which was OK with early switches, but today produces problems with interference and often when circuits are split results in a borrowed neutral a dangerous situation.
5) Before 1966 many houses had no earth to light fittings, so can't use modern equipment.
6) Quartz lights should not be dimmed as it reduces their life.

So we see people trying to get around the problems listed above, often trying to add wires, the move to LED has resulted in many old dimmers now not working, there was at one time a dimmer that fitted in ceiling rose with of course a remote control, but the model sold by B&Q would not work with LED bulbs, they were liked where there was also a ceiling fan, as lights could be off and fan on.

There are some cleaver ways around lack of wires, MK do I think it called Echo where the moving of the switch generates a radio signal to work a relay else where, so you have a switch with no wires, there are also versions with batteries in the switch back box, as far as I know these will not dim.

We call twin and earth a cable, it has three wires, there is also a triple and earth often used with dimmers and two way switching to bring in the extra wire, which could be line or neutral.

So explain what you want to do, we will try to help, the dimmer switches in my house have all been removed, they were no good with quartz and now moving to LED there is no ambiance, the colour change was wanted as well as less light, and not seen a dimmer which has remote control and no neutral and my living room lights have remote control.
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