My husband has changed 5 light fittings from chandelier type lights to ordinary ceiling pendant lights, all of them were wired the same, there is just 3 wires coming from the ceiling (black, red and yellow/green) which he wired into the ceiling rose and everything worked fine ...but one of the lights is staying on even when the light switch is off, it is wired exactly the same way as the other 4 lights and the 3 wires from the ceiling all look identical to the ones in the other light fittings...any ideas on how to fix this?
he refitted the old chandelier type light fitting and it works fine, have also tried different ceiling roses and they also stay on when the light switch is turned off...
In the main there are four wires to a ceiling rose. 1) Earth (after 1960) 2) Neutral normally black or blue. 3) Permanent line normal centre terminal red or brown. 4) Switched line likely originally black or blue with a sleeve making it red or brown but often this sleeve is missing so one has to be careful to identify it.
Often three cables into a ceiling rose not including the flex. 1) Supply in. 2) Supply to next lamp. 3) Switch wires. End of radial there will be only two cables and there is nothing to stop having two supplies to next lamp.
Also where designed for transformer use often the switch box is used instead of ceiling rose as the junction box. However the design of the ceiling rose system means less cable so better loop impedance and also easy to fit emergency lamp or ceiling fan so most follow the ceiling rose standard. But this is a British thing and lamps from abroad often don't have the connection for permanent line.
Clearly he has selected permanent line instead of switched line.
Most common DIY error is to connect the switched line direct to neutral causing a short circuit pre colour change there was a twin and earth cable with two reds and a bare earth for use as switch wires but as we went to new colours the twin brown with a bare earth never seemed to be made so wires are over sleeved.
DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!