NCCER Electrical Certification Practice Test

The common colors for 120-volt circuit wiring in the U.S. are black for the hot wire, white for the neutral wire, and green or bare for the ground wire. This color code is established by the National Electrical Code (NEC) and is widely adhered to in electrical installations across the country.

Black is typically used for the hot conductor as it is the standard color for carrying current. The white wire serves as the neutral in a circuit, providing a return path for the electrical current. The green wire or bare wire is designated for grounding purposes, ensuring safety and reducing the risk of electrical shock or fire.

Using these color codes helps electricians and anyone working with electrical systems easily identify the purpose of each wire, promoting safe installation practices and maintaining consistency in electrical work throughout different projects and environments.