I am attempting to fit a new light fitting, expecting it to be straight forward. But the light either remains permanently on or permanently off - ie. the switch isn't working.

At the switch I have one red, one black and one earth wire. Coming from the ceiling I have two reds, one black and one earth.

I'd assumed that I should connect both red wires to the live terminal on the new light fitting and the black wire to the neutral. But, as I said, this results in the light being constantly on.

Any thoughts or suggestions would be appreciated.

Thanks.

Darren, November 2008

Did the light work with the old fitting as it looks as though there will be another junction box somewhere .

A useful bit of kit is a Mains Neon Test Screwdriver which lights up if the tip touches a live wire or connector..

This will mean that the wires at the ceiling and also the switch can be checked to see which is the live , the switched live and the neutral.

Basically the live is fed from a common point (ceiling rose OR a junction box in the ceiling void) to the switch . The other side of the switch then goes to the ceiling rose as a "switched live " (marked with a red band )and connects to one side of the light fitting/bulb. The other side is the common neutral.


If this doesn`t make any sense to you then seek professional help as electricity is very dangerous.

Don`t guess where the wires go !

sparky man, November 2008

Lord Finchley tried to mend the Electric Light
Himself. It struck him dead: And serve him right!
It is the business of the wealthy man
To give employment to the artisan.

The ususal arrangement in the UK is that a cable with black and red wires goes from the ceiling to the switch - power goes out on the red wire and comes back on a BLACK wire (when the switch is on) - this must have an identifying red (brown) sleeve on it to show that it's switched live - i.e Dangerous and NOT a Neutral wire - this wire connects to the pendant flex Brown wire.

What you describe is very scary - you are missing a black wire in the ceiling (probably the switched live) and could easily have a nasty accident - get an electrician in.

Peccavi, November 2008