Electromagnetic relay is an electronic control device. It has a control system (also called an input loop) and a controlled system (also called an output loop). It is usually used in automatic control circuits. It actually uses a smaller current and a lower current. A kind of "automatic switch" to control a larger current and a higher voltage. Therefore, it plays the role of automatic adjustment, safety protection, and conversion circuit in the circuit.
Electromagnetic relay is an important component in electric bells, telephones and automatic control circuit devices. Its essence is a switch controlled by an electromagnet. It plays a role similar to a switch in the circuit: controlling high voltage and strong current with low voltage and weak current; Realize remote control and automatic control.
The use of electromagnetic relays can use low voltage and weak current control circuits to control high voltage and strong current working circuits, and can realize remote control and production automation. Electromagnetic relays are widely used in automatic control (such as refrigerators, cars, elevators, machine tools) In the control circuit) and the communication field.