This diagram illustrates a switch and receptacle in the same outlet box located in the middle of the circuit. This wiring allows the electricity to continue from the receptacle, on to any other outlets in the circuit and it provides a switch to control a light fixture or other load, such as another receptacle or a fan.
Here the exhaust fan is controlled by a timer instead of a switch. There should be two hot wires and a ground coming out of the timer casing, splice one of these to the hot source. Spice the second to the black, cable wire running to the fan. Splice the source neutral to the white cable wire and the ground to the ground wires. At the fan splice the wires, matching the colors of each.
This diagram illustrates wiring a GFCI receptacle and light switch in the same outlet box, a common arrangement in a bathroom with limited space. The hot source is spliced to the LINE terminal on the receptacle and to the bottom terminal on the light switch. The neutral and ground wires are spliced together and run to each device in the circuit.
In this diagram, two receptacle outlets are wired in the same box with a separate 120 volt source feeding each. Three-wire cable runs into the box. The black and red wires are hot and each is connected to one of the receptacles. The white, neutral wire is splice to each outlet so they share the return path. This is appropriate for standard duplex receptacles, but should not be used for GFCI receptacles. GFCI’s must have dedicated neutral connections to work properly.