3-Way Switch Wiring - Power Source and Fixture Feed on Different Switches

This article discusses how to wire a three-way power source and a fixture on different switches.

At the ceiling box--the ungrounded conductor (a.k.a. hot) from the fixture connects to the black wire from the switch. The white wire from the switch is the grounded leg conductor (a.k.a. neutral) for the fixture. Bare wires are together and grounded to box (if metallic) and if the fixture has a green wire or a grounding screw, it gets grounded also. Bares and green wires are equipment grounding conductors.

If You Need Onward Power From the Fixture:

If only switched power required onward then at existing fixture:

• Onward cable--black/white/bare
• Connect black from onward cable to the black coming from switch
• Connect white from onward cable to white wire coming from switch
• Connect bare from onward cable to other bares and to electrical box if metallic
• At the onward cables destination, the black is the switched ungrounded conductor (a.k.a. hot), the white is the grounded leg (a.k.a. neutral), and the bare is the equipment grounding conductor.

If Only Unswitched Power Required Onward then at Existing Fixture:

• This is not possible with this configuration as there are no unswitched ungrounded conductors available at the fixture/ceiling box location

• At switch 1 location--only unswitched onward power is available. At Switch 2 location--only switched onward power is available

If Only Unswitched Power Required Onward then SWITCH 1 LOCATION:

• Onward cable -black/white/bare
• Connect black from onward cable to the black coming from
• Circuit power supply cable
• Connect white from onward cable to white wire coming from circuit power supply cable
• Connect bare from onward cable to other bares and to electrical box if metallic
• At the onward cables destination, the black is the ungrounded conductor (a.k.a. hot), the white is the grounded leg (a.k.a. neutral), and the bare is the equipment grounding conductor

If Only Switched Power Required Onward then at SWITCH 2 LOCATION:

• Onward cable--black/white/bare
• Connect black from onward cable to the black coming from fixture
• Connect white from onward cable to white wire coming from switch 1
• Connect bare from onward cable to other bares and to electrical box if metallic
• At the onward cables destination, the black is the switched ungrounded conductor (a.k.a. hot), the white is the grounded leg (a.k.a. neutral), and the bare is the equipment grounding conductor

The Common screw of a 3 way switch is the Odd color screw

If wiring multiple fixtures be sure to check the following guidelines concerning how to do it and what not to do: Wiring Multiple Fixtures.

If you are new at understanding the "politically correct" electrical terminology and need clarification of the terms used, we strongly urge you to read the Clarification of Definitions and Terminology guide. This will explain the terminology used in this article.