What are the three basic parts of a relay?

Relays can be divided into contact and non-contact forms. There are many types according to their functions, such as light, sound, electromagnetic, temperature, air pressure, water pressure, air pressure, etc. The subject may be asking about intermediate relays, which are mainly magnetic Circuit, moving reed combination, static contact combination, these three components form an intermediate relay like a thermal relay, which is composed of a double gold system and a conversion contact (roughly part, there are many small parts) like non-contact The relay at Dot usually touches the solid state relay. Its internal semiconductor circuit has no contacts and the controlled current is relatively large.