Which color indicates a 20-amp circuit in an electrical system?

In an electrical system, the color black is typically used to indicate a 20-amp circuit. This color coding is part of the National Electrical Code (NEC) standards and helps electricians and technicians quickly identify the appropriate circuit ratings. Generally, black wires are used for hot electrical circuits, and in residential wiring, a black wire is standard for circuit ratings up to and including 20 amps.

The other colors mentioned serve different purposes in electrical systems: red is usually associated with second hot wires in a 240-volt circuit, green indicates ground wires, and white is typically reserved for neutral wires. Understanding these color codes is crucial for ensuring safety and proper functionality in electrical installations.