Relay and its main functions

时间:2019-10-10 17:32
Relay is an automatic switching device with isolation function, which is widely used in remote control, telemetry, communication, automatic control, mechanical and electrical integration and power electronic equipment, and is one of the most important control components.
Relays generally have a certain input variables (such as current, voltage, power, impedance, frequency, temperature, pressure, speed, light, etc.) of the sensing mechanism (input), the control circuit to achieve the "pass", "broken" control of the actuator (output), the input and output parts of the relay, as well as the input amount of coupling isolation, functional processing and the output part of the intermediate mechanism (driver).
As a control element, the relay has the following functions:
1) expand the scope of control. For example, when the control signal of the multiple contact relay reaches a certain value, it can be changed by the different forms of the contact group, and the connection, the opening and the connecting circuit are switched on.
2) enlarge. For example, sensitive relay, intermediate relay, etc., with a very small amount of control, can control a lot of power circuit.
3) integrated signal. For example, when a plurality of control signals according to the provisions of the form of multi winding relay, after a relatively comprehensive, to achieve a predetermined control effect.
4) automatic, remote control, monitoring. For example, the relay and other electrical appliances in the automatic device can form the program control circuit, which can realize the automatic operation.