ABB contactor uses main contact to open and close circuit and auxiliary contact to execute control command. The main contact usually has only normally open contact, while the auxiliary contact often has two pairs of normally open and normally closed contacts. Small contactors are often used as intermediate relays to cooperate with the main circuit.

交流接触器的接点，由银钨合金制成，具有良好的导电性和耐高温烧蚀性。ABB小型接触器的动作动力来源于交流电磁铁，电磁铁由两个“山”字形的幼硅钢片叠成，其中一个固定，在上面套上线圈，工作电压有多种供选择。为了使磁力稳定，铁芯的吸合面，加上短路环。交流接触器在失电后，依靠弹簧复位。

The contact of AC contactor is made of silver tungsten alloy, which has good conductivity and high temperature ablation resistance. ABB small contactor is driven by AC electromagnet. The electromagnet is made up of two "mountain" shaped young silicon steel sheets, one of which is fixed and covered with coil. There are various working voltages to choose from. In order to stabilize the magnetic force, a short-circuit ring is added to the pull-in surface of the iron core. AC contactor in the power loss, rely on spring reset.

另一半是活动铁芯，构造和固定铁芯一样，用以带动主接点和辅助接点的开短。20安培以上的接触器加有灭弧罩，利用断开电路时产生的电磁力，快速拉断电弧，以保护接点。交流接触器制作为一个整体，外形和性能也在不断提高，但是功能始终不变。无论技术的发展到什么程度，普通的交流接触器还是有其重要的地位。

The other half is a movable iron core with the same structure as the fixed iron core, which is used to drive the opening and closing of the main contact and auxiliary contact. The contactors with more than 20 amperes are equipped with arc extinguishing cover. The electromagnetic force generated when the circuit is disconnected can quickly pull off the arc to protect the contact. AC contactor as a whole, shape and performance are constantly improving, but the function is always the same. No matter to what extent the technology develops, ordinary AC contactor still has its important position.

小型接触器其实就是一种短路保护器，广泛用于配电系统喝控制系统，主要进行短路保护或严重过载保护。工作时，熔断器串连在被保护的电路中。当电路发生短路或严重过载时，熔断器中的熔断体将自动熔断，起到保护作用，常见的就是保险丝。

In fact, small contactor is a kind of short-circuit protector, which is widely used in power distribution system and control system, mainly for short-circuit protection or serious overload protection. When working, the fuse is connected in series in the protected circuit. When the circuit short circuit or serious overload, the fuse link in the fuse will automatically fuse, play a protective role, the common is the fuse.

另外还有断路器,俗称"空气开关",也是一种短路保护器,当过流时,它会自动跳闸,起到保护作用;熔断器、断路器都是保护电器。但它们不是一样.断路器是总称，它分为两种——框架式断路器和塑料外壳式断路器。

In addition, there is a circuit breaker, commonly known as "air switch", which is also a kind of short-circuit protector. When it is over-current, it will trip automatically and play a protective role; Fuses and circuit breakers are protective appliances. But they are not the same. Circuit breaker is a general term, it is divided into two kinds - frame circuit breaker and plastic case circuit breaker.

框架式断路器俗称万 能断路器；塑料外壳式断路器俗称空气开头。他们具有短路和过载保护，可重复使用。寿命一般在几千次到几万次。熔断器是靠熔体熔化保护线路的一种电器，不可重复使用，保护以后需要更换熔体。

Frame circuit breaker is commonly known as universal circuit breaker; Plastic case circuit breaker is commonly known as air circuit breaker. They have short circuit and overload protection and can be reused. The life span is from thousands to tens of thousands of times. Fuse is a kind of electrical equipment which depends on the melt to protect the circuit. It can not be reused and needs to be replaced after protection.