In this light switch wiring diagram the power feed joins the circuit via the light fixture where a two wire cable c2 runs from the light to the first 3 way switch sw1 and a 3 wire cable c3 joins the two switches. Three wire cable runs between the switches and 2 wire cable runs to the light.

Wiring A 3 Way Switch
3 way switch diagram power to light. Wiring diagram for a 3 way switch one of the many wiring diagrams showing different methods of wiring a three way switch circuit. With these diagrams below it will take the guess work out of wiring. 3 way switch wiring diagram with power feed via light. The black and red wires between sw1 and sw2 are connected to the traveler terminals. 3 way switch wire diagrampower to light fixture. Traveler wires are interchangeable.
3 way switch wiring diagram depicting all wires in the ceiling junction box. In the above 3 way switch wiring diagram at each switch the black wire gets connected to the copper or black screw. Wiring diagram 3 way switch with light at the end. This three way light switch wiring diagram shows how to do the light switch wiring and the light when the power is coming to the light fixture. In this diagram the electrical source is at the first switch and the light is located at the end of the circuit. Regardless of what 3 way switch wiring diagram youre following youll need to use a 3 wire cable to connect the two 3 way light switches.
In this diagram power enters the fixture box. Wiring a 3 way light switch. With a pair of 3 way switches either can make or break the connection that completes the circuit to the light. A 3 wire nm connects the traveler terminals of the first and second 3 way switch together. This might seem intimidating but it does not have to be. 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.
Interested in a 4 way switch wiring diagram. The black hot wire connects to the far right switchs common terminal. Pick the diagram that is most like the scenario you are in and see if you can wire your switch. So what you should see if you have correct 3 wire electrical cable romex is a black power white neutral and now a 3rd red wire. Take a closer look at a 3 way switch wiring diagram. In the 1st diagram below a 2 wire nm cable supplies power from the panel to the first switch box.
Typical 3 way switch wiring nm cable. In the ceiling light fixture electrical box one black wire from a 3 way switch gets connected to the black load wire on the light fixture. Now discussing 3 way light switch wiring diagram as also discussed above the color codes of the wires as having three insulated conductors as black as hot red as switch wire or called traveler and white as common wire as also shown when light is connected to both black and white wires. This electrical wiring diagram shows power into light switch box 1 wire to light from switch box 1 and from switch box 1 to three way light switch box 2. The black line wire connects to the common terminal of the first 3 way switch.