Quck answer
To wire two switches to one light fixture, you will need a 3-wire cable with a ground. First, turn off the power supply. Connect the black wire from the power source to the common terminal of the first switch. Connect the black wire from the light fixture to the common terminal of the second switch. Connect the red and white wires from the power source to the remaining terminals of both switches. Finally, connect the white wire from the light fixture to the white wire from the power source. Make sure to secure all connections with wire nuts and test the switches before turning the power back on.
Special switches known as three-way switches are required when connecting two switches to a single light fixture. These switches are referred to as single-pole, double-throw (SPDT) switches and have three terminals. They control a single circuit but can be in one of two positions depending on the position of the other switch.
Three-way switches must always be wired in pairs, and there are three different configurations that affect how you connect the switches. In all configurations, you need an additional hot wire to connect the switches, which can be achieved by using three-conductor cable.
Here is what you need to know about connecting two switches to control one light fixture.
General Procedure for Wiring Switches
Before wiring any electrical device, you must first feed the cable to the electrical box mounted on the wall and ensure that the power is off. It is always a good idea to test wires with a noncontact voltage tester before touching them.
When wiring a simple switch, at most two cables are required: one that supplies power (line cable) and one that feeds the fixture (load cable). The switch interrupts the hot leg of the circuit, so the black wires from the line and load cables are connected to the switch terminals. Since the return leg of the circuit bypasses the switch, the white wires are twisted together and capped. When the switch comes after the fixture, there is no return wire. Instead, there is a single cable with the white wire taped black to indicate that it is hot, and both this and the black wire are connected to the switch terminals.
Wiring Two Switches Before the Light Fixture
Three-way switches have three terminals: two are brass, and one is black, known as the common. When both switches come before the light fixture, one will be closer to the power source, and the other will be nearer to the fixture. Here’s how to wire the one closest to the power source:
- Connect the black line wire to the common terminal.
- Connect the red and black wires that join the switches together to the two brass terminals.
- Twist the white wires together and cap them.
- Twist or clamp the ground wires together and connect them to the green ground terminal on the switch.
For the second switch, follow these wiring instructions:
- Connect the red and black wires from the first switch to the brass terminals.
- Connect the black load wire (going to the fixture) to the common terminal.
- Twist and cap the white wires.
- Connect ground wires to the ground screw.
Wiring the Other Configurations
In the first of the other two configurations, the line cable comes to the fixture.
To wire a three-way switch, follow these steps:
1. Join the black wire to the white wire going to the first switch, and wrap black tape around the white wire to indicate that it’s hot.
2. At the first switch, splice the white wire taped black to the white wire going to the second switch, and connect it to the common terminal on the second switch.
3. Connect the white wire to the neutral terminal on the fixture and the black wire going to the first switch to the hot terminal.
4. Connect the black wire from the fixture to the common terminal on the first switch.
5. Finish by connecting the red and black wires between the switches to the brass terminals on the switches.
If the fixture is between the switches, wire the switch that has the line cable first:
1. Connect the black hot wire to the common terminal and the red and black wires going to the second switch to the two brass terminals. Splice the white wires together.
2. At the fixture, connect the white wire from the first switch to the neutral terminal and the black wire going to the second switch to the hot terminal. Splice the red and black wires together to continue on to the second switch. Since you just used the black wire from the second switch, you have to use the white wire as a hot wire. Wrap that wire in black tape on both ends and splice it to the black wire coming from the first switch.
3. Finish at the second switch by connecting the red wire and the white one with black tape to the two brass terminals and connecting the black wire to the common terminal.
FAQ
1. Can I wire two switches to control one light fixture?
Yes, it is possible to wire two switches to control one light fixture. This is known as a “three-way switch” setup. To achieve this, you will need two three-way switches, a light fixture, and some electrical wiring. The wiring process involves connecting one switch to the power source and the other switch to the light fixture. The switches are then connected using a traveler wire. This setup allows you to control the light fixture from either switch, providing convenience and flexibility.
2. What are the benefits of wiring two switches to one light fixture?
Wiring two switches to control one light fixture offers several benefits. Firstly, it allows you to conveniently control the light from multiple locations, such as having switches at both ends of a long hallway. This eliminates the need to walk back to the original switch to turn off the light. Additionally, it provides flexibility in how you use the space, as you can choose which switch to use based on your location. It also adds a layer of safety, as you can easily turn off the light from either switch in case of an emergency.
3. How do I wire two switches to one light fixture?
To wire two switches to control one light fixture, you will need to follow specific steps. Firstly, turn off the power supply to the circuit you’ll be working on. Then, install the two three-way switches in the desired locations. Next, run a traveler wire between the two switches, connecting the corresponding terminals. Connect the power source to one switch and the light fixture to the other switch. Finally, connect the ground wires and test the setup to ensure it is working correctly. It’s crucial to understand the wiring diagram and follow safety precautions when working with electrical systems.