Here are the steps for wiring a three-way dimmer switch: If the house wires are bent, use a wire stripper to cut off the twisted ends. Remove 3/4 inch of casing from the end of the house wires and the dimmer switch wires, if needed. Connect the ground wire from your dimmer to a green or bare copper wire in the wall box.. In the diagram below, a 2-wire NM cable supplies power from the panel to the dimmer box. The black (line) wire connects to the common terminal of the 3-way dimmer. A 3-wire NM connects the travelers of the dimmer to the travelers of the 3-way switch. Traveler wires are interchangeable on each switch. The 3-way dimmer and 3-way switch are also.
The black (or red) wire is the "hot" wire that carries the electrical power, the white wire is the neutral wire, and the green or copper wire is the ground wire. Step 4: Connect the dimmer switch Your dimmer switch will have three wires - a black or red wire, a green or copper wire, and sometimes a third wire (usually red or blue) that might be.. In the diagram, the power supply enters from the left. As you can see, the 2-way switch is solely being used to control the black wire. It doesn't matter if you use a brass or silver screw; you have a black hot wire coming in that goes to one screw on the side of the 2-way switch, and a black wire coming from the other screw on the 2-way switch that goes to the load (light, ceiling fan e.t.c).