Relays usually consist of the following components and modules:
![](https://oss.icku.net/icku/information/0_227191.png)
2. Contact: The core part of the relay, used to control the switch of the circuit.
3. Spring: used to control the closing and opening of contacts.
4. Magnet: used to attract and release contacts to achieve switching action.
5. Housing: used to protect the internal components of the relay, and also serves as a heat dissipation and protection.
6. Connection terminal: used to connect the relay to the external circuit.
7. Auxiliary modules: such as light indication, overload protection, delay function, etc., are used to enhance the functions and performance of the relay.