Silver Tungsten Alloy Contactors Moudel US-N50 For Power Distribution

Contactors are divided into AC contactors (voltage AC) and DC contactors (voltage DC), which are used in power, power distribution and power consumption. Broadly speaking, contactor refers to an electrical appliance that uses the current flowing through the coil to generate a magnetic field and close the contact in order to control the load. main features The AC contactor uses the main contact to open and close the circuit and the auxiliary contact to turn on the control circuit. The main contact is generally normally open contact, while the auxiliary contact often has two pairs of normally open contact and normally closed contact. Small contactors are often used as intermediate relays to cooperate with the main circuit. The contact of AC contactor is made of silver tungsten alloy, which has good conductivity and high temperature ablation resistance. The power of AC contactor action comes from the magnetic field generated by AC through the coil with iron core. The electromagnet core is composed of two "mountain" shaped young silicon steel sheets. One of the fixed iron core is sleeved with coil, and the working voltage can be selected. In order to stabilize the magnetic force, a short-circuit ring is added to the suction surface of the iron core. After the AC contactor loses power, it returns by spring. The other half is a movable iron core, whose structure is the same as that of a fixed iron core, which is used to drive the closing and breaking of the main contact and auxiliary contact. Contactors above 20 amps are equipped with arc extinguishing cover, which can quickly break the arc and protect the contact by using the electromagnetic force generated when the circuit is disconnected. The contactor can operate at high frequency. When it is used as the power on and off control, the maximum operation frequency can reach 1200 times per hour. The service life of contactors is very long. The mechanical life is usually millions to 10 million times, and the electrical life is generally hundreds of thousands to millions of times. working principle The working principle of the contactor is: when the contactor coil is energized, the coil current will generate a magnetic field. The generated magnetic field causes the static iron core to generate electromagnetic suction to attract the moving iron core, and drives the AC contactor to act. The normally closed contact is disconnected and the normally open contact is closed. The two are linked. When the coil is powered off, the electromagnetic suction disappears, and the armature is released under the action of the release spring to restore the contact, open the normally open contact and close the normally closed contact. The working principle of DC contactor is a little similar to that of temperature switch.