Above is a wiring diagram for a standard, 3-way lamp switch. This socket is used with a three way bulb containing 2 separate elements that are energized separately and then together as the switch knob is turned, for varying degrees of light.
This type of switch will be referred to as a 2 circuit lamp switch when shopping at home stores. Don’t mistake this for a three way switch (pictured below), the two do not function in the same way.
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.
The plain wire is the hot. If the cord isn’t marked with a bead then the strands of wire will be different colors. In these cases the silver wire is the neutral and the brass colored wire is the hot. The plug on the lamp cord holds another clue to polarity with the wide prong being the neutral and the narrow one the hot. Older lamp cord will have prongs that are the same size. This is because polarity was not observed on electric lamps until the development of grounded circuits.
These sockets have two terminals, one for the hot wire and one for the neutral. A third contact may be present but is not used for this circuit. This diagram illustrates wiring for a standard, one setting lamp. This socket has two terminals, the brass for hot and the silver for the neutral wire.
This diagram shows the wiring for a switch to control multiple receptacles. The source for the circuit is at the switch and the receptacles are wired using pigtail splices to make the connections.
This circuit breaker wiring diagram illustrates installing a 30 amp circuit breaker for a 240 volt circuit. The 10/3 cable for this circuit has 3 conductors and no ground. A 30 amp circuit like this is usually found in water heater circuits and older installations for clothes dryers and kitchen ranges. For a new installation of a kitchen range, use the diagram below for a 50amp circuit.
This is a wiring diagram for an antique floor lamp with 4 bulbs, one main bulb and 3 peripheral, and usually smaller bulbs. The main bulb threads into a standard socket with an integrated switch and the three peripheral bulbs are wired to a single switch. The secondary switch may have wires colored black, blue and red or, if it’s an old switch, other colors or texturing may be used to distinguish them.