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Tips for Wiring Electrical Outlets and Switches


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Mark the Three Way Switch Common Wire
3-way switch

3-Way Switch Common and Traveler Terminals

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Three way switches control a light fixture or outlet from two different locations. These switches have two "traveler" wires and a "common" wire.

The trick in replacing an old switch is to mark the COM or common wire off the old three way switch before you replace the old switch so that you properly connect the COM wire to the new 3-way switch's dark or bronze screw terminal identified as COM. The COM wire is the one you have to install to a specific switch terminal screw. With the other two traveler wires it makes no real difference to which terminals they get fastened.

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