What does the term "branch circuit" refer to within an electrical system?

The term "branch circuit" is defined specifically as a portion of an electrical distribution system that extends from the final overcurrent protective device to the outlet(s). This means that a branch circuit encompasses all the wiring and devices that are connected downstream of the circuit breaker or fuse, which provides overcurrent protection. It typically includes any junction boxes, switches, and outlets that receive power from that protection device.

In an electrical system, branch circuits are essential as they deliver power to various loads, whether they be outlets, lights, or any other appliances. The NEC emphasizes the importance of properly identifying and installing branch circuits to ensure both safety and efficiency in electrical installations. This definition aligns with the National Electrical Code guidelines, which provide standards for safe electrical installations and help prevent issues such as overloads or electrical fires.

The other choices do not accurately capture the complete definition of a branch circuit. For instance, while some branch circuits may indeed only power lighting fixtures, this does not encapsulate the full range of their application. A branch circuit can supply power to any type of load, not just lighting, thus making the first option the most complete and accurate description.