A 3 wire nm connects the traveler terminals of the first 3 way switch and the first 4 way switch. With alternate light switch wiring an nm cable supplies line voltage from the electrical panel to a light fixture outlet box.
How to wire a wall switch.
Wall switch wiring diagram. Another reason to change out the switch is appearances. Electric wall switches last a long time. This diagram shows the wiring for multiple switched outlets on one switch.
3 not intended for critical medical or life support equipment. A 3 way switch circuit is explained and described in detail including visual animation and practical application. This is an updated version of the first arrangement.
Another nm cable connects from the light fixture box to the switch box. In the 1st diagram below a 2 wire nm cable supplies power from the panel to the first switch box. They have two screw terminals plus a ground screw.
At the outlets each is wired using a pigtail splice to make the hot and neutral connections. Video includes the bonus addition of adding a 4 way switch. The red and black are used for hot and the white neutral wire at the switch box allows for powering a timer remote control or other programmable switch.
The black line wire connects to the common terminal of the first 3 way switch. Because the electrical code as of the 2011 nec update requires a neutral wire in most new switch boxes a 3 wire cable runs between the light and switch. The switch leg.
Single pole switches are the most common light switches in a home. Typical 4 way switch wiring nm cable. One screw terminal is for the hot wire that feeds the switch from the power source.
The other terminal is for a second hot wire called a switch leg that runs only between the switch and the light fixture. The source for the circuit is at the switch and 2 wire cable runs to each receptacle outlet. In the diagram below right a 2 wire nm cable that connects the light fixture to the switch carries 2 line wires one line and one switched line.
Still you will want to replace a switch when it wears out in part because it presents a fire hazard. Go into the attic and drill a 3 4 inch hole in the top plate of the wall directly over the cutout for the new switch. Use caution when using the idevices wall switch to control any appliances which produce heat or mechanical motion or could create a hazardous condition when operated while unattended.
With this arrangement all the outlets will turn on and off at the same time. If either cable in the attic is long enough feed it through the hole down to.