Identify the ac magnetic contactor and magnetic relay

A simple introduction
Electromagnetic relay is a relay that generates a predetermined response from the relative motion of the mechanical component in the input circuit current.
The electromagnetic contactor is one of the important components in the automatic control system. When the electromagnetic coil of the contactor is electrified, produces a strong magnetic field, makes the static iron core generates magnetic force to attract the armature, and drive action contact: normally closed contact is disconnected, normally open contact is closed, the two are linked. When the coil power, the electromagnetic force disappears, the armature of the release spring release, to make the contact recovery: normally closed contact is closed, normally open contact is disconnected. In industrial electrical, the model of the contactor is a lot of electric current in the range of 5A-1000A, its use is quite extensive. In electrical engineering, the contactor is a kind of used to connect or disconnect the AC and DC main circuit with load or large capacity control automatic switch circuit, the main control object is a motor, used also for other power loads, such as electric heaters, electric welding machine, lighting device contactor can not only connect and disconnect the circuit, but also has low voltage release protective effect.
2 classification of electromagnetic contactor
(1) AC contactor. Mainly in the electromagnetic mechanism, contact system, the arc device, etc.. Commonly used is CJ10, CJ12B, CJ12 and other series.
Because the AC electromagnetic contactor coil commonly used AC power supply, after the excitation contactor, usually a high decibel “slightly” noise, which has also become the characteristics of electromagnetic contactor. Although after the 1980s, all the development of AC contactor electromagnet soundless and power-saving, one of the basic feasible solution is the AC power supply with a step-down transformer, the internal rectifier DC conversion power supply, but the complex control mode does not see more.
(2) direct current contactor. Generally used in the control of DC electrical equipment, the coil in the DC power, DC contactor of the principle and structure of the structure is the same as the AC contactor. Because it can quickly cut off the main circuit of AC and DC and can frequently connected with the current control (some types of up to 800 Amperes) circuit device, so often used in motor do for the control of the object, but also can be used as factory equipment, electric heater, machine tools and all kinds of electric power unit control power load, and as a remote control device.
(3) air type contactor. Mainly by the contact system, the electromagnetic operating system, support, auxiliary contacts and shell (or chassis).
(4) vacuum contactor. Contactor vacuum contactor for the contact system by vacuum chamber degaussing.
(5) semiconductor contactor. The contactor of the current operation of the electric current operation by the use of the circuit breaker and the circuit breaker.
Three, electromagnetic relay and contactor
The difference between electromagnetic relay and contactor is to see their specific use.
Relay (1) the main role is signal detection, transmission, transforms or processing, through breaking the circuit current is usually small, that is generally used in the control circuit and the main circuit comparison).
(2) the main effect of the contactor is to connect or disconnect the main circuit. The so-called main circuit is a circuit operation or not, whether the circuit is connected to the symbol. The concept of main circuit and control circuit. General main circuit through the current ratio control circuit. Therefore, as the first floor of a friend said, large capacity contactors are generally with the arc extinguishing cover (for high current breaking meeting to produce arc, the arc shield arc, contact burn).
However, if a main circuit works less, then it can be used as a device for the main circuit of the relay. Relay as a contactor. But if a main circuit current is very large, so that the use of on-off of the main circuit of the contactor capacity is very large, to make such of the contactor of the current is also very large. That is to say current flowing through the control circuit of the utility model is very large, with the ordinary relay to on-off control circuit. At this time, you can choose to use as a contactor to the use of electrical appliances as the control circuit is broken, the role of the contactor in this situation is the relay.