This article describes a fan or light switched separately power source at light and light controlled by two 3-way switches and fan at one location only 3-Wire (plus ground) cable being routed thru the ceiling box between switches.
At the ceiling box - the ungrounded conductor {aka hot} from the fan connects to the black wire from the switch 1. The ungrounded conductor {aka hot} for the light connects to the red wire coming from switch 2. The white wire from the circuit power supply cable is the grounded leg conductor {aka neutral} for both the fan and light. The white wire from the switch (on the black/white/bare cable) connects to the black wire from the circuit power supply cable.
The red wire on the black/red/white/bare cable coming from switch box 1 is unused and just cap it off at both ends with a insulated wire nut. This will provide a switched ungrounded conductor {aka hot} for the fan and a switched ungrounded conductor {aka hot} for the light.
The reason for using a 3 wire + ground (black/red/white/bare) cable between switch box 1 and fixture (and not using the red wire) is to ensure that it will be easy to distinguish at the fixture the difference with the 2 cables coming from switch box 1 to help prevent the wrong two wires being connected. Using 2 wire + bares (black/white/bare) would make it more difficult to distinguish the 2 cables at the fixture and could end up with a combination of wrong wires being connected together. In certain onward power scenarios mentioned further in this article we will make use of this additional wire.
Wrap a piece of black electrical tape around both ends of all white wires going between the switch and the fixture to indicate that the wire is being used as a ungrounded conductor {aka hot}, this includes the white wire going between switch box 1 and 2, as this wire is also being used as a ungrounded conductor {aka hot}.
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.
Be sure to read all documentation that comes with your fan / light combo fixture.
If only switched power required onward then at existing fixture
If switched and unswitched power required onward then at existing fixture
If 2 separately switched power is required onward then at existing fixture
If you need onward power from the switch then....
NOTE: Onward power is only possible at switch box 1, and only thru the use of the extra wire available between switch box 1 and fixture.
If only switched power required onward then at existing switch... Only possible with one of the switches at switch box 1 location, and only after the following wiring changes aremade
1. On the 3 wire + bare (black/red/white/bare) cable between switch box 1 and fixture - remove the white wire from the 3 way switch and and connect the previously unused red wire in its place, at the fixture end remove the white wire and connect the red wire to the white that continues on to switch box 2.
2. Now you should have the white wire that goes between switch box 1 and fixture on the 3 wire + bare (black/red/white/bare) cable unused.
3. now connect that white wire to the white wire on the circuit power supply cable at ceiling box. (giving you now an grounded leg {aka neutral} available at switch box 1).
If only unswitch power required onward then at existing switch
This is only possible at switch box 1 , and the following wiring must be changed first:
1. On the 3 wire + bare (black/red/white/bare) cable between switch box 1 and fixture - remove the white wire from the 3 way switch and and connect the previously unused red wire in its place, at the fixture end remove the white wire and connect the red wire to the white that continues on to switch box 2.
2. Now you should have the white wire that goes between switch box 1 and fixture on the 3 wire + bare (black/red/white/bare) cable unused.
3. now connect that white wire to the white wire on the circuit power supply cable at ceiling box. (giving you now an grounded leg {aka neutral} available at switch box 1).
If switched and unswitched power required onward then at existing switch
Only possible with one of the switches at switch box 1 location, and only after the following wiring changes aremade...
1. On the 3 wire + bare (black/red/white/bare) cable between switch box 1 and fixture - remove the white wire from the 3 way switch and and connect the previously unused red wire in its place, at the fixture end remove the white wire and connect the red wire to the white that continues on to switch box 2.
2. Now you should have the white wire that goes between switch box 1 and fixture on the 3 wire + bare (black/red/white/bare) cable unused.
3. now connect that white wire to the white wire on the circuit power supply cable at ceiling box. (giving you now an grounded leg {aka neutral} available at switch box 1).
3 wire (plus ground) cable being routed thru the ceiling box between switches
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.