Load Centers & Circuit Breaker Boxes

A load center is a device that distributes electricity to different circuits in a building. It has a metal box with circuit breakers that protect each circuit from overloading. A load center can also be called a panelboard, a breaker box, or an electrical panel.

A load center, commonly known as a breaker box, serves as the central distribution point for electrical power in residential and smaller commercial buildings. It contains circuit breakers or fuses that control and safeguard individual circuits, supplying electricity to various areas and appliances. In contrast, a panelboard is a versatile enclosure found in residential, commercial, and industrial settings, encompassing a broader range of electrical components such as switches, meters, relays, and control devices. Panelboards are used in more complex electrical systems, while load centers are specific to simpler distribution needs in homes and smaller commercial spaces.

Some load centers have a main breaker, which is a large circuit breaker that controls the power supply to the entire load center and can shut off all the circuits at once. A main breaker also provides overcurrent protection to the load center and its branch circuits. Not all load centers have a main breaker, though. Some load centers have a main lug, which is a terminal that connects the incoming power lines directly to the load center without a circuit breaker. A main lug load center is usually connected to another load center that has a main breaker1

A load center can have different types, sizes, and capacities depending on the power supply and the number of circuits it serves. The most common type of load center is a main breaker load center, which has a main breaker that controls the power supply to the entire load center and can shut off all the circuits at once. Another type of load center is a main lug load center, which has no main breaker but connects directly to another load center that has a main breaker.