Wire A Three Way Switch
Three way switches are used to have two switches turn on light(s). They can do that because there is always power to both switches even if one of the switches is turned off. This article teaches you how to wire a three way switch.
brief how to
- Understanding Three Way Switches
- Attach the black wire from the power cable to the common terminal
- Attach the white wires to each other with a wire nut
- Use the holes in the wirestrippers to form a hook at the ends of the black wires
- Attach the wires to the brass terminals on the switch
- Attach the two white wires together with a wire connector
- If using a plastic box attach the two ground wires together and add a 6 inch pigtail to go to the gound on the switch
- If using a metal box attach the two ground wires together and add two 6 inch pigtails, one gets attached to the metal box and one gets attached to the switch
- Attach the switch to the box and test it
- Wire The light fixture
tools and materials
- 2 Three way switches
- Wire strippers
- Needlenose pliers
- Screwdriver, phillips head
- Switch box
- Wire connectors
- If using a metal box you will also need, grounding screw and cable clamps
step 1 Understanding Three Way Switches
A three way switch has 4 terminals:
- One common terminal that the power hooks up to, Brass or Black colored
- Two Traveleer terminals, Silver colored
- One Ground, Green colored
The First box: The First box has the power come into it with a 2 wire cable, and a 3 wire cable going out if it to the second box and switch.
The Second: The second box has the 3 wire cable coming in from the first box and a 2 wire cable going out to the light.
The Traveler: The 3 wire cable that goes between boxes is called the "Traveler". The 3 wire cable allows power to go to the second switch even when the first switch is turned off.
step 2 Wire The First Box
Bring the two wire power cable, from the breaker panel, into the first switch box and attach the black wire to the common terminal on the switch. (the common terminal is usually black in color)
Bring the three wire "traveler" cable into the first switch box and attach the black and red wires to the traveler terminals, (the two terminals that are the same color)
Attach the white wires from the power cable and traveler cable to each other with a wire nut.
Attach the ground wires to each other with a grounding wire nut and then attach the ground to the switch.
Push the wires into the box and screw the switch to the box.
step 3 Wire The Second Box
The 3 wire traveler cable goes from the first box to the second switch box. To hook up the second switch you will hook the black and red wires from the 3 wire traveler cable to the terminals on the switch in the same position, sides, as on the first switch.
Run 2 wire cable goes from the second box to the lights. Attach the black wire that goes to the light to the common terminal. (the power comes into the first switch on the common terminal and goes out of the seconde switch to the light(s) on the common terminal).
After the connections are made put the wires into the box and screw the switch to the box. Use wire nuts to
step 4 Wire The Light Fixture
Attach the light to the 2 wire cable. Black to Black, White to White, and Ground to Ground. Push the wires into the ceiling box and attach the light fixture to it.
Turn the breaker on and test your 3 way light switches.
Attach the switch to the box and test it.
