Each part does something special: Main Switch: This switch controls all electricity coming into the box. Busbar: A metal strip spreads power to each circuit. Also called a distribution board, panel board, breaker panel, or electric panel, it is the central hub in an electrical system that divides incoming power into various subsidiary circuits. Today, electrical systems are essential for homes and industries. While the terminology might seem overlapping, understanding the specific functions, applications, and differences between a. A distribution board (also known as a service panel or breaker box) is a centralized collection of circuit breakers, fuses, and/or relays used to control and protect the wiring in a home.