Miniature circuit breakers (MCBs) are the most widely used terminal protection devices in building electrical distribution systems. They are used for protection against short circuits, overloads, and overvoltages in single-phase and three-phase circuits up to 125A, and are available in four types: single-pole 1P, two-pole 2P, three-pole 3P, and four-pole 4P.
A circuit breaker is a mechanical switching device capable of connecting, carrying, and disconnecting current under normal circuit conditions, and also capable of connecting, carrying, and disconnecting current for a specified time under specified abnormal circuit conditions.
