How to Replace a Wall Switch

How to Replace a Wall Switch

The wall switch controls the flow of electricity to permanent light fixtures or wall outlets, shutting them ON when it's flipped up and OFF when flipped down.wall switch These switches are found in the walls of homes, apartments, condominiums and commercial buildings. They are usually regulated by some agency charged with electrical safety and standards. The dimensions, mechanical designs and overall appearance of these switches have changed slowly over the years. The types of switches available are based on the amount of control required and the desired functions, such as energy conservation or timed lighting.

The most common switch is a simple ON/OFF switch, often called a single-location switch.wall switch This type of switch turns a light (or a wall outlet) OFF or ON from only one wall location, and can be recognized by the printed ON/OFF markings on the toggle lever.

These switches are typically wired so that the black (hot) wire coming into the electrical box is spliced to one side of the switch, and the white wire is connected to the other side.wall switch When the switch is turned on, electricity flows through the wires to the fixture or outlet, and the switch "closes" the circuit. When the switch is OFF, it interrupts the current.

A variation on this type of switch is the three-way switch, which can be flipped OFF or ON at two locations.wall switch These are used in stairwells, garages or basements with two entrances where you want to be able to turn a light fixture or appliance ON or OFF from either end of the stairwell. The switch is wired so that the black wire coming in to the electrical box is spliced directly to one of the terminal screws on the switch, and the white wire is connected between the screw and the fixture. The third terminal screw on a 3-way switch is a green grounding screw, which connects to the circuit's bare copper grounding wire.

If you're replacing a switch, the first step is to make sure the power to the fixture is completely OFF by turning off the circuit breaker that serves the area in which you're working.wall switch Use a multimeter set to continuity or resistance to check for electricity. With the instrument set to read voltage, touch one probe to each darker screw terminal and the brass-colored terminal on the same side of the switch. A good, functioning switch will show continuity between the two brass screw terminals and light up when the lever is pushed toward you.

Carefully unscrew the old switch, pulling it out gently to avoid tearing the wiring. Measure the height, width and depth of the electrical box in which it's mounted to determine whether your new switch will fit. If it will, carefully remove the cover plate and mark where the screw holes are with a pencil. If the cover plate is not present, install a new one that matches the existing design. Then, using needle-nose pliers, shape each of the remaining wires to form a loop that will fit over one of the switch terminals and wrap around clockwise when tightened.