Wiring Diagrams to Add a Receptacle Outlet
–Check local regulations for restrictions and permit requirements before beginning electrical work–
–Most wiring diagrams on this site include a green dot representing the integrated grounding terminal found in most metal outlet boxes. However, some older metal boxes and most plastic boxes don't have a terminal like this.
–By code, the number of conductors allowed in a box are limited depending on its size. Conductors include wires, devices like switches and receptacles, and some other metal parts. Check here to calculate the number of conductors allowed in a box before adding new wiring, etc.
This page contains diagrams to add a new electrical outlet to an existing circuit. Arrangements are included to use an existing receptacle circuit or lights and switch circuits as the source for a new wall outlet.
Add a New Receptacle
To add a new outlet to a group of receptacles already in place, splice the new wires to one set of wires on one of the existing receptacles. In this diagram each receptacle is wired to the next using the terminals to pass the voltage along. To provide voltage to a new receptacle, remove the wires from one set of terminals on the existing outlet and splice in the new wires and a pigtail back to each terminal.
Add an Outlet from a Light Switch
This diagram shows the wiring for a new receptacle added from a light switch. The switch must have an always-hot wire for the source and a neutral wire must be present for the return path. The hot source is spliced with a pigtail back to the switch, and to a new 2-wire cable running to the new outlet. The neutral is spliced in the switch box to both the existing light, and the cable to the new receptacle.
Add a Receptacle from a Light Fixture
This circuit diagram shows the wiring for a new receptacle outlet connected at a light fixture. The source at the fixture is always hot and a switch loop controls the light. New 2-wire cable runs from the fixture box to the new receptacle and the source hot, neutral, and ground are splice to it along with a pigtail back to the fixture circuit. With this arrangement the new receptacle is always hot.
Add Receptacle to Light Fixture Circuit
Here a new receptacle is added to a light fixture circuit. The connections at the light fixture are spliced and extended to the new receptacle. With this arrangement the new receptacle will turn off and on with the light fixture.
Add a Receptacle to a 3 Way Circuit
Here a receptacle is added to a 3 way light circuit before the first switch. It is not controlled with the switches but is instead always hot. The source hot, neutral and ground are spliced to a 2-wire cable that runs to the new outlet. The 3 way switches and light are then wired in the usual way with the common on SW2 spliced to the source hot and the light hot wired to the common on SW1.