Operationally. Molded case circuit breaker adopts two sets of devices to protect overcurrent and short circuit respectively. The action value of overcurrent protection can be adjusted manually, which is convenient and rapid. The miniature circuit breaker shares a set of devices for over-current and short circuit, and the current is not adjustable, so it can not solve the problem many times. The molded case circuit breaker has large phase to phase distance and arc extinguishing cover, which has strong arc extinguishing ability, can withstand greater short-circuit current, and is not easy to cause phase to phase short circuit, so its service life is longer than that of miniature circuit breaker.

在这一方面还是塑壳断路器更加突出，其在设置的灵活性上比微型断路器更好。塑壳断路器的过流和短路保护装置是各自独立的，使用中过流保护的动作值还可以做出灵活调整。微型断路器的过流保护和短路保护是统一装置，调节灵活性上存在一定不足。

In this respect, the molded case circuit breaker is more prominent, and its setting flexibility is better than the miniature circuit breaker. The overcurrent and short circuit protection devices of molded case circuit breaker are independent, and the action value of overcurrent protection can be flexibly adjusted in use. The over-current protection and short-circuit protection of miniature circuit breaker are unified devices, and there are some deficiencies in regulation flexibility.

根据以上的情况看似乎都是微型断路器处于下风，但其实对于某些时候，还是需要选择微型断路器的。比方说需要提高线路的性时，因为微型断路器的动作灵敏度高，分断动作快，更有利于对线路及电器的保护。

According to the above situation, it seems that the miniature circuit breaker is at a disadvantage, but in fact, for some times, the miniature circuit breaker still needs to be selected. For example, when it is necessary to improve the safety of the line, because the miniature circuit breaker has high action sensitivity and fast breaking action, it is more conducive to the protection of the line and electrical appliances.

由此可以看见两者都有着各自的优点和适合使用的地方，关键是要充分了解塑壳断路器和微型断路器的区别，并根据自身的需要进行选择。

It can be seen that both have their own advantages and suitable places for use. The key is to fully understand the differences between molded case circuit breaker and miniature circuit breaker, and select them according to their own needs.