What is the difference between an air switch and a molded case
circuit breaker?
Molded case circuit breakers are also air circuit breakers. Commonly used air
circuit breakers include frame circuit breakers and molded case circuit breakers. The former has a large capacity, a large rated breaking current, and a large volume, so there is no plastic case, and all parts of the circuit breaker are mounted on a steel frame.
The capacity of the latter is relatively small, and the rated breaking current is also small, so the volume is also small, and the entire
circuit breaker is protected by a plastic shell. Generally, frame circuit breakers are used in power circuits with large currents, while molded case circuit breakers are used in load circuits.
Air switches generally play the role of "isolation" and "protection device" in small current circuits, also called automatic switches, also called air circuit breakers;
The circuit breaker has good arc extinguishing ability, and it will automatically trip when the circuit is short-circuited and high-current; in high-voltage and high-current circuits, it is often used as an operating appliance for power failure, power transmission, and connection and disconnection of loads;
Current level: Molded case circuit breakers are generally below 630A, air circuit breakers are generally above 630A, and miniature circuit breakers are generally below 63A;
Differences in voltage levels: general air switches are suitable for voltage levels below 500V, while circuit breakers are usually suitable for voltage levels above 220V;
The ability to interrupt current is different: the load and short-circuit current that general circuit breakers can withstand are larger;
The difference between arc extinguishing medium and method: the arc extinguishing medium and method of circuit breaker not only include air circuit breaker, but also vacuum
circuit breaker, oily circuit breaker, less oil circuit breaker, sulfur hexafluoride circuit breaker, etc.