Lamp Switch Wiring Diagrams
Also see:This page contains wiring diagrams for three different types of lamps. Included is a diagram for a two–circuit lamp switch to control a standard incandescent bulb on top of the lamp and a smaller, low wattage bulb in the base. Also include are diagrams for a standard one setting lamp and a three way lamp.
Lamp cords are usually one color making the standard black–hot, white–neutral guidelines useless for determining polarity. Other methods are therefore used to determine the polarity on a lamp cord. Check the insulation on the cord wires closely and you will find either a textured bead or a thin colored line running along one wire, this is the neutral. 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.
This diagram illustrates the wiring for a bedside lamp with two sockets. The top socket A, holds a standard incandescent bulb. The second socket B, typically holds a small, low–wattage bulb similar to a nightlite bulb. The switch allows for energizing the top bulb only, the nightlite only, both bulbs at once or for turning both bulbs off. This type of switch will be referred to as a 2 circuit lamp switch when shoping at home stores. Don't mistake this for a three way switch (pictured below), the two do not function in the same way.
Above is a wiring diagram for a standard, 3–way lamp switch. This socket is used with a three way bulb containing 3 separate elements that are energized in succession for varying degrees of light. These sockets have two terminals and the internal workings of the switch vary the delivery of voltage to each element as the switch knob is turned.
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.
