Contactors are divided into alternating current contactors (voltage AC) and direct current contactors (voltage DC). In the broad sense, a contactor refers to an electric field that uses a current flowing through a coil to generate a magnetic field in industrial electricity, so that the contacts are closed, so as to reach the load controlling electrical appliances.
In electrical engineering, because it can quickly cut off AC and DC main circuits and devices that can frequently switch on and off high-current control (up to 800A) circuits.
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 attraction to attract the moving iron core, and drives the AC contactor point action. Closed alternately, which are linked. When the coil is de-energized, the electromagnetic attraction force disappears, and the armature is released under the action of the release spring, so that the intermittent recovery, normally open connection, and normally closed alternately close. The working principle of a DC contactor is similar to that of a temperature switch.
The contactor can be operated at high frequency, has good conductivity and high temperature ablation resistance; the life of the contactor is very high, the mechanical life is usually millions to 10 million times, and the electrical life is generally hundreds of thousands To millions of times.
The overall development trend of the contactor will develop in the direction of long electrical life, high reliability, multi-function, environmental protection, multi-specification, intelligent and communicable.
The DC contactor permanent magnet mechanism has special electricity with low noise, no pollution, low power consumption, environmental protection and energy saving, high reliability, simple production process and low cost.
Contactors are mainly used in power, power distribution and power applications. Contactors are often used in electric motors as control objects. They can also be used to control electrical loads such as factory equipment, heaters, working machines and various power units. They are suitable for frequent operations and remote control. They are important components in automatic control systems. one.