This drawing illustrates the wiring for a split receptacle controlled by a switch. The tab connecting the hot terminals on the receptacle is removed and the source hot is connected to the bottom half. The source neutral is connected to one of the neutral terminals on the receptacle.
If, however, you’re putting in a new hardwired doorbell or you need to repair an existing one, the diagrams on this page illustrate the most common installations you will find. Included are wiring for a typical hardwired doorbell, a two-button doorbell, an old house doorbell powered by a battery, and an alternate power source using an ac adapter.
New 2-wire cable is run from the receptacle to the new light fixture. At the receptacle the wires are removed and each one is spliced to the new cable and back to the receptacle with a pigtail splice. At the light fixture box the black wire connects to the hot terminal, the white connects to the neutral terminal and the ground to any metal grounding terminal on the fixture, outlet box, or both.
With this lamp, bulb A can be turned off and on independently and switch B can turn on bulb 1 alone, bulbs 2 and 3 together with bulb 1 off, bulbs 1, 2 and 3 all on at the same time or all three off.
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.
The neutral and ground wires for the circuit are connected to a bar along the side of the service panel box. The neutral and grounding bars in the box may be separate or, in the case of older service panels, the same bar may be used for both purposes.
This wiring diagram illustrates wiring a light switch to control an existing receptacle outlet. The source is at the receptacle and a switch loop is added to a new switch. The hot source wire is removed from the receptacle and spliced to the red wire running to the switch. The black wire to the switch connects to the hot on the receptacle.
A doorbell circuit for two or more doors will have a separate contact on the chimes for each button included. At the chimes, one wire from each button is spliced to the output wire on the transformer. The second wire is connected to one of the contact screws on the chimes.