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In modern UK properties, the lighting circuits are distinct from the ring main circuit. Houses should generally have two lighting circuits that are protected by either a 5A fuse or 6A trip located in the consumer unit.

The lighting circuit differs from the ring main in that it does not create a returning loop to the consumer unit. Instead, the consumer unit connects to the first light, which connects to the second light, and it continues.

For domestic lighting, the cable is earth rated for up to 12A, and contains live, neutral, and earth wires inside its PVC sheath. The cable leads from the consumer unit to the lighting locations on ceilings or walls. The power for the lights is either connected at the switch, or directly on the light itself.

If the light switch is wall mounted, the box can either be affixed sunk into the wall, or as a surface-mounted fixture. If you wish to minimise the number of wall switches in a single room a multi-switch unit can be installed, allowing more than one light to be operated from one point.

To install the lights themselves, the wiring will either to a ceiling rose or a junction box. If it is a ceiling fixture, all the connections at the ceiling rose point. This does eliminate the need for one junction box per light/lamp, but it is a trickier task for a home installer to undertake.

With older lighting installations, the cable is passed through the junction box particular to that light. The junction box itself will be located under floorboards or between joists in the ceiling close to the switch. Like fluorescent lights, lighting systems that do not use a ceiling rose must have junction box connections.

Here are some of the different lighting types that you may consider for domestic or commercial installation:

Fluorescent