Moulded case circuit breaker and frame circuit breaker are both very common products in circuit breaker products. However, many people do not fully understand the differences between the two, and they are often hesitant when purchasing. Some of the customers I face often have such troubles. Here we first understand the concepts of the two, and then understand the differences between the two, Learn about the choice of the two.

1、兩者外觀及安裝尺寸不同：

1. They are different in appearance and installation size

首先從外觀上，兩者的尺寸不同，框架斷路器尺寸、體積較大，塑殼斷路器尺寸及體積相對較小。

First of all, from the appearance, the size of the two are different, the size and volume of the frame circuit breaker are larger, and the size and volume of the molded case circuit breaker are relatively small.

2、兩者適用范圍不同

2. The scope of application of the two is different

框架斷路器的額度電流自400A至6300A，主要用于配電網(wǎng)絡(luò)中，用來分配電能，保護線路和電源設(shè)備，使免受過載，欠電壓，短路、單相接地等故障的危害；

The rated current of frame circuit breaker ranges from 400A to 6300A. It is mainly used in distribution network to distribute electric energy and protect lines and power supply equipment from overload, undervoltage, short circuit, single-phase grounding and other faults;

塑殼斷路器的額度電流自10至800A，用于在配電線路中線路和設(shè)備發(fā)生過載、短路、欠壓時，對線路和設(shè)備提供保護，也可對電動機的不頻繁啟動提供過載、短路、欠壓保護。

The rated current of moulded case circuit breaker is from 10 to 800A, which is used to provide protection for lines and equipment in case of overload, short circuit and undervoltage in distribution lines, and to provide overload, short circuit and undervoltage protection for infrequent starting of motor.

一 級配電設(shè)備，統(tǒng)稱為動力配電中心，它們集中安裝在企業(yè)的變電站，把電能分配給不同地點的下級配電設(shè)備。這一 級設(shè)備緊靠變壓器側(cè)，故電氣參數(shù)要求較高，輸出電路容量也較大，一般在主配電柜中，主要元器件框架斷路器。

Primary distribution equipment, collectively referred to as power distribution center, are installed in the enterprise's substation to distribute power to lower level distribution equipment in different locations. This level of equipment is close to the transformer side, so the requirements of electrical parameters are high, and the output circuit capacity is also large. Generally, in the main distribution cabinet, the main components are frame circuit breakers.

二 級配電設(shè)備，是動力配電柜和電動機控制中心的統(tǒng)稱。動力配電柜使用在負荷比較分散、回路較少的場合；電動機控制中心用于負荷集中、回路較多的場合。它們把上一 級配電設(shè)備某一電路的電能分配給就近的負荷。這級設(shè)備應對負荷提供保護、監(jiān)視和控制，一般選擇使用的斷路器：塑殼斷路器、微斷開關(guān)等。

Secondary distribution equipment is the general name of power distribution cabinet and motor control center. The power distribution cabinet is used in the situation where the load is scattered and the circuit is less; Motor control center is used in the situation of concentrated load and more circuits. They distribute the electric energy of a certain circuit of the upper level distribution equipment to the nearest load. This class of equipment shall provide protection, monitoring and control for the load. Generally, the circuit breakers used are moulded case circuit breakers, micro break switches, etc.

3、使用類別不同

3. Different use categories

塑殼斷路器使用類別通常A類，在短路情況下，選擇性保護無人為短延時，因而無短時耐受電流（Icw）值；

The type of MCCB is usually class A. in case of short circuit, the selective protection is short time delay, so there is no short-time withstand current (ICW);

框架斷路器使用類別通常B類，在短路情況下，選擇性保護有人為短延時（可調(diào)節(jié)），因而有短時耐受電流（Icw）值；

The type of frame circuit breaker is usually class B. In case of short circuit, the selective protection has artificial short time delay (adjustable), so it has short time withstand current (ICW);

具體使用，需根據(jù)負載情況，選擇不同的斷路器產(chǎn)品。

For specific use, different circuit breaker products should be selected according to the load.