Two way light switches

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This is the way of controlling one light from two different switches.

The difference between this and one way is basically down to the switches and the link cable between them. The switches will have two 'ways' and therefore three terminals each.

Switch off the power supply at the consumer unit, and remove the fuse for the circuit from which you are going to take the supply for the new light.

Instal the switches and cables

Mount both of the two way switches in their respective positions and run a suitable three core and earth cable between them.

Run a suitable two core and earth cable from the nearest switch back to the light fitting position.

At the switch with one cable,

strip and prepare the cable ready for connection, remembering to sleeve the earth conductor with green and yellow insulation.

Connect the three core cable as follows:

Red to the terminal labelled ‘C’ – common.

Yellow to the terminal labelled ‘L1’.

Blue to the terminal labelled ‘L2’.

Green/yellow to the terminal marked with the earth symbol.

At the switch with two cables,

Now repeat the process at the switch with two cables, but here, also connect the two core and earth cable as follows, having tagged the black with a piece of red insulation tape:

Red to the terminal labelled ‘L1’ which also houses the yellow of the three core cable.

Black tagged with red to the terminal labelled ‘L2’ which also houses the blue of the three core cable.

Green/yellow to the terminal marked with the earth symbol.

Connecting the light

The ceiling rose, light fitting and the supply cable may now be connected in the same way as for one way lighting.

Double check all your work and make sure all covers have been replaced.

Once you are sure that all work has been completed correctly, replace the fuse for the circuit, switch the power back on, and test.

• One way lighting
• Lighting circuits