A branch circuit is an electrical circuit within a customer facility that goes from a breaker in the main service panel to serve a specific amount of load in the facility. An individual branch circuit serves just one piece of equipment such as an air conditioning unit or an electric oven. A general-purpose branch circuit provides power to multiple outlets and lights. Each circuit typically consists of two wires: a hot wire and a neutral wire. In addition to the neutral wire, a grounding wire also returns to the main panel and, from there, is connected to a ground.
Branch circuits are designed so that the amount of load connected to any specific circuit does not exceed the current-carrying capacity of the wire. If load reaches a specific limit, the breaker in the service panel will open, thus protecting the wiring from damage.