3-way switchesallow us to turn a light fixture on and off from two different locations.
From a wiring perspective, you could spot a 3-way switch using the number of screw terminals.
There will be four in total: three terminal screws, plus a ground screw.
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Two of the terminals are a light bronze or copper, and are calledtravelers.
The single dark-colored screw is known as thecommonterminal, and the ground screw is usually green.
3-Way Switch Basics
The most importantwireto get right is the hot wire connected to each switch’scommonscrew terminal.
This is usually black, and carries power from the source to each switch and the light fixture.
The twotravelerterminals are used to connect the “traveler” wires, which are also considered hot.
The other wires are the neutral (usually white) and ground (usually bare copper or green).
The neutral wire bypasses both 3-way switches, connecting to the light fixture.
The ground connects to the ground terminal on each switch, and to the light fixture.
check that the power is off at both switch boxes using anon-contact voltage tester.
No, most codes only require one 3-way switch box to have a neutral wire available.
If your three-way switch iswired wrongyour light will not work from both locations.
Wiring issues could also impact power throughout the rest of the area.
The white neutral wire will likely be leading into a cap, or wire nut.
