According to the principle of action, relays can be divided into the following categories:
1. Solid state relay:
A relay in which the input and output functions are performed by electronic components without mechanical moving parts.
2. Electromagnetic relay:
A relay that generates a predetermined response from the relative motion of mechanical components. It includes DC electromagnetic relay, AC electromagnetic relay, magnetic holding relay, polarization relay, energy saving power relay, tongue spring relay.
3. Time relay:
When an input signal is added or removed, the output part needs to be delayed or timed before the relay of its control line is closed or disconnected.
4. Acceleration relay:
When the acceleration of the moving object reaches the specified value, the controlled circuit will be switched on or off.
5. Wind speed relay:
When the wind speed reaches a certain value, the controlled circuit will be switched on or off.
6. Temperature relay:
The relay operates when the external temperature reaches a specified value.
7. Other types of relays:
Such as optical relay, sound relay, thermal relay and so on.
Relay has many advantages such as fast operation, stable operation, long service life and small size. Widely used in power protection, automation, motion, remote control, measurement and communication devices.