Common Household Switches & Functionalities

Common Household Switches

Woman turning off light switch on beige wallpapered wall, close-up

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As you walk into your home, the convenience of switches light the rooms of your home. They complete the circuit to your light fixtures when you turn the switch on to light the light and they break the circuit when you turn off the switch to turn the light off.

Switches control lighting, turn on and off devices and are used as disconnecting means for things like furnaces in your home. There are many different switches that are used throughout the home, depending on the specific needs of that area of the home. There are switches for one location and others for many locations, There are also switches that dim the lights for those special moments. 

A standard switch will still turn the lights on and off just fine, but the construction of the commercial type is more stout and with better contacts. You know what they say, "You get what you pay for." The commercial switch will last longer due to heavier contacts for switching longevity. Some hardware stores may list commercial grade switches as their "Pro" grade switches.

If you've ever noticed that when you flip the switch on or off and there's a snap, crackle, or pop, then it's pretty clear that your switch is defective and it's time to replace it. In fact, switches will sizzle like a fine T-bone steak when the contact gets really worn. It is almost a spooky feeling as you hear the contacts arcing. This is a potential electrical hazard that will continually get worse as the contact area erodes away until the contact points are pitted. This causes resistance and heat build-up, which to lead to an electrical fire at some point. 


If you hear the sizzling sound, chances are the contacts are arcing and the switch is heating up. This is not good. Get it shut off as soon as possible and shut of the circuit. You will actually be able to smell the plastic burning as the contacts get hot enough to melt the plastic switch parts.

Single-pole switches are the most basic switches. They simply turn a light on and off. They come in a variety of colors and are rated for 15 and 20 amps.

Three-way switches control lights from two different locations. By adding a four-way switch between them, you can control lighting from three locations. Common uses for three-way switches are hallways, stairwells, or large rooms like living rooms with more than one doorway in them.

Dimmers switches control a lights brightness or intensity. These switches use rheostats to brighten or dim the lights and are a glorified single-pole switch with options. Dimmer switches often replace single-pole switches in homes. These switches work just fine with incandescent lighting, but specialized dimmer switches are required for ceiling fans and fluorescent lights.


Single Pole Switches

A single-pole switch turns a light on and off from one location. The switch has two brass terminals for the "hot" wire connections and a green screw for the ground connection. The toggle handle on the switch is labeled on and off.

Three-way Switches

A three-way switch has two brass screws, a darker colored screw and a green screw. The brass screw is the traveler wire connections. The darker colored screw is for either the "hot" wire or the switch leg. The green screw is for the ground connection. Unlike the single-pole switch, the three-way switch doesn't have the toggle handle switched. That's because one position doesn't mean that is necessarily on or off. It always depends on the position of the other switch. Learn more about three-way switches.

Rotary Dimmer Switch

A rotary dimmer switch is a switch with a rheostat that is used to dim the lights via the switch. Some rotary dimmer switches turn off and others have to have the knob pressed in to shut them off. By turning the knob to the left, the lights will get dimmer. Turning the knob to the right will make them brighter. This is a great switch if you're using accent lighting. Learn more about rotary dimmer switches.