How to Wire a Three Way Switch
Nov 13, 2022
A 3-way switch is very handy as it enables you to switch on the lights from two different parts of the home. Sometimes people get confused about wiring a 3-way switch because it is not as common as a traditional, one-way switches.
But if you've installed a single pole switch, following this guide should be easy. This guide will teach you how to wire a 3-way switch through a step-by-step process.
What is a 3-Way Switch?
A switch that has three screw terminals for electrification connections and allows for a light fixture to be controlled from two different locations.
How do You Wire a 3-Way Switch?
With a 3-way switch, there is an extra wire called the traveler because it joins two switches with each other.
Follow the given steps to do the wiring of a three-way switch correctly.
1. Turn Off The Power At Circuit Panel
Go to the power circuit at your home and turn off the lower for the particular breaker where the 3-way switch is placed.
Tip: Recheck the circuit panel to see if the power is appropriately off.
2. Draw Out The Previous Switch
Open up the switch plate by removing the screws and checking the last switch. Also, lose up the fasteners that are keeping the control in place. Carefully pull the switch from the hole.
3. Identify The Wires
In a three-way switch, the black wire is called a common wire which is hot as it carries the electricity from the power source to the primary switch.
- Black wire: The black wire is the load or hot wire that carries the voltage through the switch. In a light switch, the black wires connect to the brass screws on the sides of the switch, referred to as the terminal screws.
- White wire: The white wire is known as the neutral wire.
- Copper wire: The bare copper wire, that is not covered, is considered the ground wire. It can also be green or green with a yellow stripe. In the switch, the ground wire is attached to the green grounding screw.
4. Pin Down The Common Wire And Label It
There are typically five wires in a box:
● Two neutral white wires
● A red wire
● A black wire
● Black wire attached to the black screw extreme or copper called common wire.
Label the 3-way switch common wire with tape so it will be easy to distinguish it later.
5. Identify Wires In Second Box
In the second box, there are only four wires.
● A black wire
● A red wire
● A white wire
● A ground wire
Mark on the white wire shows that it is a hot wire. The common wire in the box is the black one which combines with the terminal. Tag the white wire for easy identification.
6. Disjoint The Wires
Once you label specific wires and get an idea about what each wire does, disconnect them. Loose the screws from the terminal by twisting off the nuts of the wire. The uncovered wire ends will get visible, which does not connect to the switch anymore.
7. Install And Connect The New 3 Way Switch
Finally, attach the new three-way switch but ensure that both switches are identical.
Check for the terminals and common wires in the new switches you install. With common terminals, connect the common wires.
Now attach the red wires at the exact location of the upper right or left part of the switches in both boxes.
Connect the second traveler wire of both boxes to the open upper ends, which are not utilized by the red wire.
With the help of a wire nut, twist the neutral white wires and then turn and fix the three ground wires in the primary box. Attach the shortest ground wire terminal with the green end of the switch.
Now move towards the second box and join the ground wire to the switch's brass or green end screw.
8. Place Switch Covers And Test Switches By Turning On The Power
Once all the wires are correctly attached, close the switches into the box. Reinsert the switch plate shields. Turn on the power source from the circuit panel.
Finally, test the switches by turning them off and on.
In this guide, we explained the 3-way switch wiring in detail in the most straightforward steps. Remember to turn off the circuit panel's power before continuing the wiring.