塑壳断路器一般适用于供电系统400V供电与低压配电系统的总进线端处接口，在地铁站被广泛运用于二级负荷小动力电源配电箱、三级负荷小动力电源配电箱、双电源切换箱、消防控制柜以及MCC柜系统中;车辆段和区间所部分低压配电系统也使用了塑壳断路器。地铁站低压配电系统中使用的断路器的型号一般是VL160、VL250等，表示额定电流为160A、250A。

Moulded case circuit breaker is generally applicable to the interface between 400V power supply of power supply system and main incoming line end of low-voltage distribution system. It is widely used in secondary load small power supply distribution box, tertiary load small power supply distribution box, dual power switch box, fire control cabinet and MCC cabinet system in Metro Station; Moulded case circuit breakers are also used in some low voltage distribution systems of depot and section post. The type of circuit breaker used in the low-voltage distribution system of subway station is generally vl160, vl250, etc., indicating that the rated current is 160A, 250A.

塑壳断路器的工作原理

Working principle of moulded case circuit breaker

低压断路器的主触点是靠手动操作或电动合闸的。主触点闭合后，自由脱扣机构将主触点锁在合闸位置上。过电流脱扣器的线圈和热脱扣器的热元件与主电路串联，欠电压脱扣器的线圈和电源并联。

The main contact of low voltage circuit breaker is manually operated or electrically closed. After the main contact is closed, the free tripping mechanism locks the main contact in the closing position. The coil of the over-current release and the thermal element of the thermal release are connected in series with the main circuit, and the coil of the under voltage release is connected in parallel with the power supply.

当电路发生短路或严重过载时，过电流脱扣器的衔铁吸合，使自由脱扣机构动作，主触点断开主电路。

When the circuit is short-circuit or seriously overloaded, the armature of the over-current release will pull in to make the free release mechanism act, and the main contact will disconnect the main circuit.

当电路过载时，热脱扣器的热元件发热使双金属片上弯曲，推动自由脱扣机构动作，主触点断开主电路。

When the circuit is overloaded, the thermal element of the thermal release will generate heat to bend the bimetallic sheet, push the free release mechanism to act, and the main contact will disconnect the main circuit.

当电路欠电压时，欠电压脱扣器的衔铁释放，也使自由脱扣机构动作，主触点断开主电路。

When the circuit is under voltage, the armature of the under voltage release releases, which also makes the free release mechanism act, and the main contact disconnects the main circuit.

当按下分励脱扣按钮时，分励脱扣器衔铁吸合，使自由脱扣机构动作，主触点断开主电路。

When the shunt release button is pressed, the armature of the shunt release is closed to make the free release mechanism act, and the main contact breaks the main circuit.

以上就是ABB塑壳断路器代理小编为大家介绍的关于塑壳断路器的相关内容，希望可以帮助到大家，更多的精彩内容可以直接关注：http://www.jntongyu.com

The above is what ABB MCCB agent Xiaobian introduces to you about MCCB. I hope it can help you. More wonderful contents can be paid attention to directly http://www.jntongyu.com