Switch off the power at the consumer unit and remove the fuse for the circuit.
Remove the old fitting.
Junction box lighting circuit
If you have a junction box type lighting circuit there will be only one cable emerging from the ceiling.
Feed the cable through the backplate of the new fitting and secure the backplate through the ceiling to the joists. If needs be, mount a wooden block between two joists to provide a fixing.
These fittings tend to retain heat, so the cable should be protected with heat resistant sleeving.
Protect all exposed earth conductors with green/yellow sleeving.
Connect the conductors to the terminals on the light fitting – brown (old cable colour = red) to live, blue (old cable colour = black) to neutral, and green/yellow to the earth terminal on the backplate. Mount the light on the backplate.
Junction box lighting circuit
If you have a loop type lighting circuit, the multitude of conductors cannot be accommodated in the fitting. Take the cables back up into the ceiling area and wire them into a securely mounted four terminal junction box. Ensure that the connections made exactly replicate those originally made in the rose. See ceiling rose cable identification
Allocate one terminal for live in, live out, and live to the switch.
Allocate one terminal for live from the switch.
Allocate one terminal for neutrals.
Heat resistant cable
Run a length heat resistant cable from this junction box. Connect the conductors to their corresponding terminals, being sure that the live picks up from the terminal housing the live from the switch.
At the light fitting, feed the other end of the cable through the backplate which can then be mounted as described above. Make the connections for the conductors as before – brown (old cable colour = red) to live, blue (old cable colour = black) to neutral and green/yellow to the earth terminal on the backplate.
Mount the light fitting on its backing plate taking care not to damage the wires.
Fittings with no backplate.
As the wiring regulations require the terminals and unsheathed sections of cables be protected in a non combustible housing, it will be necessary to fit a BESA box flush with the ceiling surface to comply. Check that this has suitable fixing positions for your light fitting.
Cut out the ceiling to accommodate this and fit a wooden support above to provide a suitable means of fixing.
Feed the cable through the BESA box and secure the box in the ceiling.
Connect the conductors to their appropriate terminals at the light fitting before securing it to the BESA box.
Replace all covers and, once you are sure that all work has been completed correctly, replace the fuse for the circuit, switch the power back on, and test.