Light Switch Wiring Diagram - Easy Whether you have power coming in through the switch or from the lights, these switch wiring diagrams will show you the light. Light Switch Wiring Diagram (Single Pole) This light switch wiring diagram page will help you to master one of the most basic do it yourself projects around your house How to wire a light switch | Downlights Wiring a One Way Switch. A one way light switch has two terminals which is a common marked as COM or C. The common is for the live wire that supplies the input voltage to the switch. The other terminal is marked as L1 and is the output to the light fixture. Light Switch Wiring Diagrams - Do-it-yourself-help Multiple Light Wiring Diagram. This diagram illustrates wiring for one switch to control 2 or more lights. The source is at SW1 and 2-wire cable runs from there to the fixtures. The hot and neutral terminals on each fixture are spliced with a pigtail to the circuit wires which then continue on to the next light. How To Wire A Three-Way Light Switch | CPT Wiring a three way light switch. Wiring of 3-way light switches is certainly more complicated than that of the more common single-pole switch, but you can figure it out if you follow our 3-way switch wiring diagram. With a pair of 3-way switches, either switch can make or break the connection that completes the circuit to the light. two-way-switching-wiring-diagram | Light wiring 2 way light switch (3 wire system, new harmonised cable colours) 2 way switch (3 wire system, old cable colours) 2 way switch (two wire control) Three way switching. 3 way light switching (new cable colours) 3 way light switch (old cable colours) 3 way light switch using a two wire control; News & Updates; Open Menu. Light wiring diagram 2 way switch wiring diagram | Light wiring There is a chance that if your house has these old wiring colours the switch drops may be from a loop-in-loop-out radial lighting circuit done with junction boxes rather than ceiling roses as shown in Fig 2. The switch wiring is all the same but the switch wire (cable C) leads up to a different set up.