Wiring a 3-way light switch involves connecting three terminals or screws on each switch. A 3-way switch setup allows you to control a single light fixture from two different locations, such as at the top and bottom of a staircase or at opposite ends of a hallway. Below is a step-by-step guide on how to wire a 3-way light switch:
Materials and Tools Needed
- Two 3-way light switches
- Electrical tape
- Wire cutter/stripper
- Screwdriver (usually Phillips head)
- Electrical wires (typically black, white, and red)
- Voltage tester (optional but recommended for safety)
- 14-2 NM-B
- 14-3 non-metallic sheathed cable (NM-B)
- 6-in. copper pigtails
- Electrical tape
- Wire nuts
Step 1: Turn Off Power
Before starting any electrical work, turn off the power to the circuit at the breaker box to prevent the risk of electrical shock.
Step 2: Identify Existing Wiring
Identify the wiring setup in your electrical box. You should have a black (hot) wire, a white (neutral) wire, and a red (traveler) wire. The black wire is the hot wire that carries power from the breaker to the switches and the light fixture. The white wire is the neutral wire, and the red wire is the traveler wire used to connect the two switches.
Step 3: Install the First Switch
- Connect the black wire (hot) from the power source to the common terminal (usually a dark-colored screw) on the first switch.
- Connect the white wire (neutral) to the silver-colored screw terminal on the same switch.
- Connect the red wire (traveler) to one of the brass-colored screw terminals on the switch.
Step 4: Install the Second Switch
- Connect the black wire (hot) from the light fixture to the common terminal on the second switch.
- Connect the white wire (neutral) to the silver-colored screw terminal on the same switch.
- Connect the red wire (traveler) to the other brass-colored screw terminal on the switch.
Step 5: Grounding
Ensure that both switches are properly grounded. This typically involves connecting a green or bare copper wire to the grounding screw on each switch. If your electrical box is metal, it should already be grounded.
Step 6: Test the Wiring
Before closing up the electrical box and restoring power, test the wiring with a voltage tester to ensure there is no electricity running through the circuit.
Step 7: Secure the Switches
Carefully fold the wires into the electrical box and screw the switches into place, making sure they are properly aligned and level.
Step 8: Restore Power and Test
After securing the switches, restore power to the circuit at the breaker box. Test the switches to ensure they are functioning correctly. Flip one switch, then go to the other location and flip the other switch to see if the light turns on and off from both locations.
Step 9: Cover Plates
Install cover plates over the switches to protect the wiring and provide a finished look.
Important Tips:
- Always turn off the power before working on any electrical wiring to prevent accidents.
- Follow local electrical codes and regulations when wiring switches.
- If you’re unsure about any aspect of the wiring process, consult a licensed electrician for assistance.