Circuit breakers, contactors, intermediate relays, thermal relays, buttons, indicator lights, universal transfer switches and travel switches are the eight most common components in electrical control circuits. The editor introduces the principles and applications of common electrical components with pictures and texts. Get a handle on how these components work in normal times by understanding their role in the electrical circuit.

1. Circuit breaker

Low-voltage circuit breakers are also called automatic air switches, which can be switched manually, and can be used to distribute electric energy, start asynchronous motors infrequently, and protect power lines and motors. Automatically cut off the circuit.

◆Outline drawing of commonly used circuit breakers

2. Contactor

The contactor is composed of two parts, the electromagnetic mechanism and the contact system. The common coil voltages of the contactor are AC220V, AC380V and DC220V. The electromagnetic mechanism of the contactor is composed of a coil, a moving iron core (armature) and a static iron core; the contactor contact system is composed of two parts, the main contact and the auxiliary contact, the main contact is used to switch the main circuit, and the auxiliary contact is used to control in the circuit.

◆Outline pictures of commonly used contactors