1. Moulded case circuit breaker

塑壳断路器，英文简称为MCCB，这种断路器的主要作用为低压配电系统和电动机保护回路中的过载、短路提供保护功能。由于其可靠性和稳定性，使之成为工业上应用十分广泛的产品。

MCCB (moulded case circuit breaker) is mainly used to protect overload and short circuit in low voltage distribution system and motor protection circuit. Because of its reliability and stability, it has been widely used in industry.

2、微型断路器

2. Miniature circuit breaker

微型断路器，英文简称为MCB，使用范围和数量都极 大的断路器产品，主要功能是为建筑电气终端配电装置提供保护。由于两者同属于断路器，且塑壳断路器多用于小容量的通断。

MCB, short for MCB in English, is a circuit breaker product with a wide range of applications and a large number of applications. Its main function is to provide protection for building electrical terminal distribution devices. Because both of them belong to circuit breaker, and MCCB is mostly used for small capacity on-off.

塑壳断路器与微型断路器的区别：

Differences between MCCB and MCB:

1、电流等级

1. Current class

塑壳断路器电流等级高2000A的都有.而微型断路器大电流等级在125A以内。

Moulded case circuit breakers have high current class of 2000a, while miniature circuit breakers have high current class of 125A.、

由于两者在容量上的差距，在具体工作中，塑壳断路器的有用面积也大于微型断路器，同时接入的导线也比较粗，可以达到35平方以上，而微型断路器只适合接10平方以下的导线。

Due to the difference in capacity between the two, the useful area of MCCB is larger than that of MCB in specific work, and the connecting wire is thicker, which can reach more than 35 square meters, while MCB is only suitable for connecting wires less than 10 square meters.

一般对于室内情况，房间较大的更适宜选择塑壳断路器。

Generally for indoor conditions, the larger room is more suitable to choose MCCB.

2、安装方式

2. Installation method

塑壳断路器以螺钉安装为主，容易压紧，接触良好，运行稳定。而微型断路器主要是通过导轨安装，有时候由于力矩不够而引发接触不好。由于两者不同的安装方式，从而导致塑壳断路器的安装比小型断路器更稳固，难度也更低。

Molded case circuit breaker is mainly installed with screws, which is easy to press, has good contact and stable operation. The micro circuit breaker is mainly installed through the guide rail, sometimes due to insufficient torque and poor contact. Due to the different installation methods, the installation of MCCB is more stable and less difficult than miniature circuit breaker.

3、操作与寿命

3. Operation and life

操作上看。塑壳断路器对过流和短路采用两套装置分别保护，过流保护动作值可以人工调整，方便迅速。而微型断路器对过流和短路共用一套装置，电流不可调，导致很多时候无法解决问题。

In terms of operation. Moulded case circuit breaker adopts two sets of devices to protect over-current and short circuit respectively. The action value of over-current protection can be adjusted manually, which is convenient and rapid. The miniature circuit breaker shares a set of device for over-current and short circuit, and the current is not adjustable, which leads to many problems that can not be solved.

塑壳断路器相间距离大，且有灭弧罩，灭弧能力强，能承受更大的短路电流，且不易引发相间短路，从而使用寿命也比微型断路器校长。

Moulded case circuit breaker has large phase to phase distance, and has arc extinguishing cover, strong arc extinguishing ability, can withstand larger 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.

4、使用灵活 性

4. Flexibility of use

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。

In this aspect, MCCB is more prominent, and its setting flexibility is better than MCB. The over-current and short-circuit protection devices of MCCB are independent, and the action value of over-current protection can be adjusted flexibly.

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。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。

The over-current protection and short-circuit protection of miniature circuit breaker are unified devices, and there are some shortcomings in regulation flexibility. According to the above situation, it seems that the miniature circuit breaker is at a disadvantage, but in fact, for some times, it is still necessary to choose the miniature circuit breaker.

比方说需要提高线路的安 全性时，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。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。

For example, when we need to improve the safety of the line, because the micro circuit breaker has high sensitivity and fast breaking action, it is more conducive to the protection of the line and electrical appliances. It can be seen that both of them have their own advantages and are suitable for use. The key is to fully understand the difference between MCCB and MCB, and choose according to their own needs.