Replacing a light switch or upgrading to a Smart light switch should be a simple DIY task for any homeowner. However, it becomes a different story when you get behind the plate. What if you make a mistake? What are all these different colored wires for? What do light switch colors mean?

Let’s look at how colors in wiring are set up to shed some light on the subject. Hopefully, you’ll find new confidence in your ability to take on minor DIY projects.

National Standards

To prevent accidents, the United States has a standard for wire colors set by the National Fire Protection Association (NFPA). This organization sets the color key that all builders, contractors, and manufacturers must follow for code compliance.

Basic Wire Coloring

If you’ve already taken off the switch plate, you’ve seen a tangle of colored wires connecting to and fro from parts unknown.

Light switch wiring is usually one of the more basic configurations.

Black wires

Black wires are “live wires.” That means that you can assume they are carrying electricity from the panel to your switch. These wires power whatever they’re connected to, so be careful when examining them.

Alternatively, the live wire may also be white with black tape on it to indicate that it’s powered.

Red wires

Red wires are also “live” and carry electricity to the switch. You may see red wires for three- or four-way switches that require an additional power supply. They’re also used on ceiling fans where the fan and light each require a dedicated power source.

White wires

White wires are considered “neutral,” but their purpose is to carry electrical power back to the panel. That means there is a possibility that they are actually “live.”

These neutral wires may also be gray in color. White or gray wires marked with black or red electrical tape are actively “live.” It pays to be cautious and handle these as though they are live for safety reasons.

Green wires

Green wires are for grounding. In case of a short circuit, power surge, or overload, this series of grounding wires will “earth” excess electrical power.

Earthing, or grounding, carries this burst of electricity to the ground through low-resistance wires back to the panel and into a metal rod buried in the ground.

Grounding prevents fires and reduces the chance of electrical shock.

When to Call in a Professional

Older homes may not have a grounding system, and you’ll only see red and white wires behind the switch plates. If this is a case, your home is a poor candidate for DIY electrical work.

Also, if you’re one of the 5 percent of Americans with colorblindness, you’re better off calling in a technician. These four colors are only the basic colors, and if your home is older, it may not meet current color codes at all.

Make an appointment today with the pros at Mr. Sparky of Pleasantville, and error on the side of caution for more complicated electrical work.