Contactor structure description

Contactor refers to an electrical appliance that uses a current flowing through a coil to generate a magnetic field in an industrial power to close the contacts to achieve a controlled load. The contactor consists of an electromagnetic system (iron core, static iron core, electromagnetic coil) contact system (normally open contact and normally closed contact) and an arc extinguishing device.

The AC contactor uses the main contact to open and close the circuit, and the auxiliary contact to turn on the control loop.

The main contacts are generally normally open contacts, while the auxiliary contacts often have two pairs of normally open contacts and normally closed contacts. Small contactors are often used as intermediate relays in conjunction with the main circuit.

The contact of the AC contactor is made of silver-tungsten alloy and has good electrical conductivity and high temperature ablation resistance.

The power of the AC contactor is generated by the magnetic field generated by the AC core coil. The electromagnet core is composed of two "mountain" shaped young silicon steel sheets. One of the fixed iron cores is sleeved with a coil, and the working voltage can be various. select. In order to stabilize the magnetic force, the suction surface of the iron core is added with a short-circuit ring. The AC contactor is reset by a spring after power loss.

The other half is a movable iron core, which is constructed like a fixed iron core to drive the closing and disconnecting of the main contact and the auxiliary contact.

The contactor of 20 amps or more is equipped with an arc extinguishing cover, and the electromagnetic force generated when the circuit is disconnected is used to quickly break the arc and protect the joint.

The contact device can be operated at high frequency. When used as power on and off control, the maximum operating frequency can reach 1200 times per hour.

Contactors have a very long service life, typically ranging from a few million to ten million mechanical lifetimes, and electrical life typically ranging from hundreds of thousands to millions of times.

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Label: Structure description of the contactor

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