Eaton 3 Way Switch Wiring. They are always installed in pairs and use special wiring connections. Find this Pin and more on electricity by Ricardo Guzman.
The upstairs is dark, and as she flips the switch. Three-way wall switches control a light fixture from two locations in a room. Three-Way Switch Wiring: Facts and How-To.
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They allow you the ability to turn the lights on or off from either location.
Three-way switches can commonly be found at either end of a hallway, near the doors of a very large room with multiple entryways or at the top and bottom of a set of stairs. The top countries of suppliers are China. I'm new to the site, and a certified electrician.