Electrical Wire Color Guide

Making a minor upgrade to your home may require you to take a look at your wiring. If you have a home with wiring installed sometime in the second half of the 20th Century or later, it probably follows a common color guide. Understanding the uses of the different colors helps you to determine the best methods for your project.

Before you start examining the wires in your electrical system, it is safe to assume that any of them could be carrying a load at the time. An imbalanced system often puts pressure on neutral or ground wires that would not ordinarily carry a current. If you have any doubts about your wiring or rewiring projects, consult with a professional beforehand.

What Do Electrical Wire Colors Mean?

Black is the standard for hot wires. These wires will usually carry an active load that is commonly called live or hot. You should assume that all wires with black insulation are live.

Wires with red insulation are also usually live or hot. In most cases, they will act as a second live wire to a black one, or as a way to connect a smoke detector to the home’s system.

Yellow or blue wires are often used as switch legs to control the load to certain wiring systems, like lighting or ceiling fans. They are the wires that go through a conduit, not typically to an outlet.

White or gray wires act as neutral wires, which can be deceiving. They may carry a current, as their purpose returns excess electricity back to the service panel.

Many grounding wires have a layer of green insulation. The goal of grounding a wire is to give a safe place for excess electricity to move without injuring people or continuing to damage the system. Ground is not conductive in the way that metal and even people can be conductive.

Bare Copper
Sometimes, ground wires are made out of bare copper instead of having green insulation. These wires are meant to provide additional protection to the circuit in the event of a surge. Although they may not have an active current, it is wise to assume that they could.

What If My Wires Are Marked With Electrical Tape?

Some wires may be marked with electrical tape to change their purpose. It changes the wire’s purpose from the typical to something else. For example, a white insulated wire with black or red tape indicates a possibly hot wire. Although you might see white wires with different colors, the opposite is usually not the case. Wire colors that are typically classified as live or hot should not be used or marked as neutral.

Hire Tidal Electrical Services for Electrical Upgrades

For most electrical system repairs and upgrades, it is best to hire a professional electrician. Electricians can update your system to your specifications without putting you or your system at risk. We can also complete the project more quickly and accurately. Contact Tidal Electrical Services to learn more.