The universal circuit breaker-also known as the air circuit breaker-is a mechanical switching device capable of making, carrying, and breaking current under normal circuit conditions, as well as making, carrying for a specified duration, and breaking current under specified abnormal circuit conditions. Universal circuit breakers are utilized to distribute electrical energy and to provide protection for power lines and source equipment against faults such as overload, undervoltage, and short circuits.
Typically, this type of circuit breaker features a steel frame within which all its components are mounted. Characterized by its high capacity, it can accommodate various types of trip units and numerous auxiliary contacts; furthermore, it possesses superior breaking capacity and thermal stability. Consequently, it is frequently deployed in applications requiring high breaking capacity and selective protection.