Some switches are operated with keys, timers, or photoelectric eyes that sense daylight. Other switches are paired up with electrical outlets (“combination” switches). You say it’s hard to find a switch in the dark? For that situation, you need a switch with a pilot light. Outdoor switches, mounted in a special waterproof electrical box, are operated with a lever that protects against shock.
Switches should match the amperage and voltage ratings for the electrical circuit they serve. And if your home has aluminum wiring, be sure the switches attached to that wiring are designated “CU-AL” for compatibility—otherwise, they can present a fire hazard.
The simplest and most common light switch is actually referred to by hardware dealers and electricians as a “single-pole light switch.” With a single-pole light switch, flipping the lever up completes the circuit, turning lights or appliances on, and flipping it down breaks the circuit, turning lights or receptacles off.
A single-pole switch has two brass terminal screws on the side that receive the black wires of the circuit. Modern single-pole switches also have a green grounding screw that connects to the circuit’s ground wire (not shown in the illustration at left).
The type of switch that will operate hallway lights from either end of the hallway is called a three-way switch; it has an extra terminal.
