Liputan6.com, Jakarta Many people want to control their lights from two different places in their home. Knowing how to wire a three-way switch can solve this problem and make your home more convenient. This electrical project helps you turn lights on and off from multiple locations.
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A 3-way switch is a special type of light switch that works with another 3-way switch. These switches let you control one light or a group of lights from two different spots. They are very useful for stairs, long hallways, and rooms with two doors.
In this article, we will talk about how to wire a 3-way switch by yourself. We will also talk about how a three-way switch works and when to use it. We gathered the guide from various sources, Sunday (9/7/2025).
How to Wire a 3 Way Switch
Before you start learning how to wire a 3-way switch, you must turn off the power at the circuit breaker. Safety is the most important part of any electrical work. Use a voltage tester to make sure no electricity flows through the wires before you begin.
Tools:
- 4-in-1 screwdriver
- Non-contact voltage tester
- Utility knife
- Wire strippers
Materials:
- 14-2 nonmetallic-sheathed cable (Type NM-B)
- 14-3 nonmetallic-sheathed cable (Type NM-B)
- 6-inch copper pigtails
- Electrical tape
- Light fixture
- Three-way switches (2)
- Wire nuts
Steps:
1. Run the Cables
First, run a 14-2 cable from your power source to the first switch location. Next, run a 14-3 cable from your first switch to the second switch. Finally, run another 14-2 cable from the second switch to the light fixture.
2. Wire the First Switch
Start by connecting the ground wires. Splice the two bare grounds from the cables to a 6-inch copper pigtail. Make a hook in the end of the pigtail and wrap clockwise around the green screw. Tighten. Next, splice the two neutrals (white wires) together. Do not attach them to the switch. The black wire from the power supply cable goes to the black common screw on the 3-way switch. The traveler wires (black and red) from the 14-3 cable go to the brass screws. It does not matter which one goes where. Wrap electrical tape around the switch to cover the exposed terminals.
3. Wire the Second Switch
Splice the two bare grounds to a 6-inch copper pigtail and attach to the green screw. Splice the two neutrals together. Do not attach to the switch. The black wire from the 14-2 cable going to the light goes to the black common screw. The black and red traveler wires from the 14-3 cable go to either of the brass traveler screws. It does not matter which traveler wire goes to which brass screw. Wrap the switch with tape.
4. Connect the Light Fixture
Make connections to the light fixture, starting with the bare copper ground wire. Connect the bare copper wire to the green ground screw on the light fixture. Splice the white neutral from the cable to the white neutral on the light fixture. Splice the black wire from the cable to the black wire on the light fixture. Attach the light fixture to the box.
5. Test Your Work
Check that switches are secure to the boxes and add faceplates. Turn on the breaker. Test your lights by flipping on and off at each location. If something is not working, turn off the breaker before checking it out. Double-check that you have travelers on the brass screws and power on the black common. Turn on the breaker, and turn on your lights.
How Does a 3 Way Switch Work?
Understanding how a 3 way switch works helps you wire it correctly. These switches are different from regular switches because they have three screw terminals instead of two. The three terminals are one common and two traveler terminals, plus a grounding screw.
The Common Terminal
The common terminal is usually a black or dark-colored screw that is different from the traveler terminals. This terminal connects to either the power source or the light fixture. Power comes into the first switch from the power source. Two wires called "travelers" connect the first switch to the second one. Then power leaves the second switch to go to the light.
The Traveler Terminals
The two traveler terminals are usually brass-colored screws. These terminals connect the two switches together using the traveler wires. No matter which switch you flip, the light responds.
How the Circuit Works
A 3-way switch allows you to control a light or group of lights from two locations. Unlike single-pole switches, which control lights from one location, 3-ways work in pairs. You must have two of them and only two. The system functions by establishing or breaking the electrical circuit. When both switches align in the same position, the circuit completes, turning the light on. When the switches are in different positions, the circuit breaks and the light turns off.
Internal Switch Mechanism
A 3-way switch does not have the words "on" or "off" written on it. Inside each 3-way switch, there are three primary terminals: one common and two travelers. The switch has an internal mechanism that routes electrical current between the traveler wires, allowing control of the light from multiple points.
When to Use a 3 Way Switch
3 way switches are very useful in many areas of your home. Knowing when to use them makes your house more convenient and safe. These switches work best in places where you need to control lights from two different locations.
Stairways
The most common place for 3 way switches is on stairways. Install one switch at the bottom of the stairs and another at the top. This allows people to turn on the lights before going up or down the stairs. They can then turn off the lights when they reach the other end. This setup makes stairs much safer, especially at night.
Long Hallways
Long hallways are perfect for 3 way switch installation. Place one switch at each end of the hallway. People can turn on the lights when they enter the hallway and turn them off when they exit at the other end. This prevents people from walking through dark hallways.
Large Rooms with Multiple Entrances
Rooms with two or more doorways benefit from 3 way switches. Install switches near each entrance to the room. This lets people control the lights no matter which door they use to enter or leave. Large living rooms, kitchens, and bedrooms often have multiple entrances that make 3 way switches helpful.
Garages and Basements
Garages and basements are other great locations for 3 way switches. In garages, place one switch near the door from the house and another near the main garage door. In basements, install switches at the top and bottom of the basement stairs. These locations help ensure you always have light when you need it.
Outdoor Areas
3 way switches work well for outdoor lighting too. Install switches inside the house and outside on a patio or deck. This allows you to control outdoor lights from inside your home or when you are outside. Outdoor 3 way switches are especially useful for porch lights and patio lighting.
Bedrooms with Multiple Doors
Some bedrooms have doors to hallways and bathrooms. 3 way switches let you control the bedroom lights from either entrance. This is convenient when moving between rooms and helps avoid fumbling for light switches in the dark.