What is the difference between a contactor and a relay?

The current that the relay can pass is relatively small, and the current of the contactor is relatively large.

2. Category differences

There are many classifications, which are generally only used to transmit signals, and are more common in control loops. Contactor can not only transmit signals, but also control the on-off of the main circuit.

3. Different functions

The main function of relay is signal detection, transmission, conversion or processing. The circuit current it switches on and off is usually very small, that is, it is generally used for control circuit (relative to "main circuit").

The main function of contactor is to connect or disconnect the main circuit. The so-called main circuit refers to whether a circuit works or not, which is marked by whether the circuit is connected or not. The concept of main circuit corresponds to that of control circuit. Generally, the main circuit passes more current than the control circuit. Large-capacity contactors are generally equipped with arc-extinguishing covers (because large current disconnection will produce arcs, and contacts will be burned without using arc-extinguishing covers).

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