A PCB relay is an electronic switch with a single armature and two or more sets of contacts. It is soldered onto a printed circuit board to ensure circuit continuity. PCB relays come in various types. They can be thermal or electromagnetic. They should be mounted perpendicular to the direction of the armature.

A PCB relay has a similar function to a standard relay, except that it is smaller and requires more precision during mounting. In addition, PCB relays are required to adhere to specific PCB design criteria, which means they need to be mounted with care. When they're mounted properly, PCB relays can be used as standard relays.

PCB relays can be mounted directly onto circuit boards, or they can be mounted as a through-hole component. Either way, they protect other components on the board from electrical hazards.

A PCB relay has all the functions of a conventional relay but is designed to fit onto a printed circuit board. It can be low current or high-voltage, and offers galvanic isolation. The most common type of PCB relay is a through-hole model.