Lighting Circuit Wiring Diagram. Click on image to open harmonized brown blue. The source is at sw1 and 2 wire cable runs from there to the fixtures.
The junction box should be wired as shown below. This wiring diagram shows how all houses and most of commercial lighting installations are wired these days. 1 single way light via a junction box click image to enlarge note if a metal light switch is used connect the earth wire to the earth terminal on the light switch and loop to the back box.
Two way switched lighting circuits 2 3 way switched lighting circuits loop at switch lighting circuits lighting circuit diagrams for 12 and 3 way switching series and parallel circuits adding an extra light from a light switch wiring for a single loft or garage light motion sensor wiring with switched override feature.
The live is interrupted by the switch wiring and the circuit is carried on to the next junction box. From the receptacle the cable feeds a switch. Switches are shown as dotted rectangles. Using a switch wire with twin red earth.