Then blue wires are most often used as travelers for three or four way switches for instance if you have switches at the top and bottom of a staircase that control the same light thats a three way switch. Wall switches used to control ceiling light fixtures or other fixtures come in three types.
How To Wire Switches
Three way switch wire colors. With these diagrams below it will take the guess work out of wiring. Then a 4 wire cable going between the two 3 way switches and then a 3 wire cable going from the switches to the load. Wiring diagram 3 way switch with light at the end. Each 3 way switch in these examples are controlling the power source to the same load. In this diagram the incoming hot wire attaches to the first switchs common dark colored terminal. White and gray electrical wires.
This might seem intimidating but it does not have to be. The light colored terminals are the traveler terminals and are interchangeable. These switches have two light colored terminals and one dark colored terminal plus a ground screw. 3 way switch wire colorsthere is no standard for wire colors on 3 way switch travelersthe colors will vary depending on whether nm cable or conduit was used. If you find wires in either of these colors youve located the neutral wires. In this diagram the electrical source is at the first switch and the light is located at the end of the circuit.
For example a long hallway or stairway might use a pair of three way. Pick the diagram that is most like the scenario you are in and see if you can wire your switch. With nm cable the wire colors for travelers will be black and red using 3 wire cablewith conduit the wire colors for travelers could be any color. The black and red wires between sw1 and sw2 are connected to the traveler terminals. Take a closer look at a 3 way switch wiring diagram. Wires consisting of a line a load a neutral a pair of travelers and two 3 way switches.
Most common is the single pole switch the type used to control a light fixture from a single locationthe next most common is the three way switch which is commonly used to control a light fixture from two different locations. All three way switch and 2 way switch wiring diagrams have the same basic components. This 3 way switch wiring diagram shows how to wire the switches and the light when the power is coming to the light switch. The dark colored terminal is the common terminal and brings power from the source to the light fixture. Color coding on three way switches is very important. When wiring a 3 way switch circuit we will be using a 3 wire cable known as romex coming from the source such as the breaker box.
Three wire cable runs between the switches and 2 wire cable runs to the light. The two hot wires of three wire cable connect to a pair of brass colored traveler terminals on each switch. If you are trying to troubleshoot a 3 way switch operation you will need to identify the function of each wire.
Gallery of Three Way Switch Wire Colors
