Lighting Circuit Diagrams
These diagrams show various methods of one, two and multiple way switching.
L and N indicate the supply. Switches are shown as dotted rectangles. Earth wires are not shown.
One way switching
Single switch. The most basic circuit.
Two way switching, 2 wires
This arrangement would typically be used in conduit, and uses two wires between each switch. It can also be used in domestic properties by using twin+earth cable between the switches, and 1core+earth from the switches to the ceiling rose.
Two way switching, 3 wires
More common in domestic properties. Twin+earth from the ceiling rose to the first switch, and three wires between the switches, usually 3 core and earth cable.
Three way switching, 2 wires
Two wires between each switch. Likely to be found with wires in conduit. The middle switch is an intermediate type.
Three way switching, 3 wires
Three wires between the two end switches, probably using 3 core and earth cable. Usually the third wire passes the middle intermediate switch but is joined in a separate terminal block.
