2-Way Switching

2-way switching lets you control one light from two different locations — for example, at the top and bottom of a staircase. It requires 3-core T&E between the two switch positions.

Wiring Diagram

How It Works

Each 2-gang switch has three terminals: COM (common), L1, and L2.

• SW1 COM receives switch live from the rose
• SW2 COM connects to the lamp
• L1 and L2 on both switches are connected together by the strapping wires (the 3-core cable)

When the switches are in matching positions (both up or both down) current flows via L1 or L2. When the positions differ, the circuit breaks.

Cable Required

• Rose to SW1: 2-core T&E (brown = switch live, blue sleeved brown = return to lamp)
• SW1 to SW2: 3-core T&E (brown, grey sleeved brown, blue sleeved brown — all three are live at various times)

Sleeving Rule

All grey and blue cores in 2-way switch cables that carry live must be sleeved brown at both ends.