Wiring a 3 way light switch 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.
2 way light switch wiring diagram old colours.
Your lighting circuit must.
Multiple light wiring diagram.
3 way light switching new cable colours 3 way light switch old cable colours 3 way light switch using a two wire control.
The source is at sw1 and 2 wire cable runs from there to the fixtures.
This was unsafe having live electrical terminals so close to a metal wall plate.
Two way light switching 3 wire system new harmonised cable colours note.
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.
3 way switch schematic wiring diagram.
You have an incoming hot wire black going to one screw it does not matter if you use the brass or silver screw on the side of the 2 way switch and a black wire from the other screw on the 2 way switch going to the load light ceiling fan etc.
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.
Two very old three way switches are depicted in the photo above.
The way i show allows you to fairly easily add a second two way switch to an existing light switch by simply wiring them together in a certain way.
With a pair of 3 way switches either can make or break the connection that completes the circuit to the light.
Schematic diagram of new wire colours.
The grey wire in cable d is a switched live and the blue wire in cable c and black wire in cable d are permanent lives and thus should be marked with brown sheathing at each end as shown.
Notice the black wire is the only wire that we are controlling through the 2 way switch.
The switch wiring is all the same but the switch wire cable c leads up to a different set up.
A two way switch uk schematic diagram of old wire colours.
The switch wiring is all the same but the switch wire cable c leads up to a different set up.
For simplicity the earth wire is not shown in the above diagram.
Two very old three way switches.
The power source comes from the fixture and then connects to the power terminal.
You will see that there is a hot wire that is then spliced through a switch and that then goes to the hot terminal of the light.
This diagram illustrates wiring for one switch to control 2 or more lights.
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.
A 2 way switch wiring diagram with power feed from the switch light.