PCB terminal blocks are modular insulating devices that mount on a printed circuit board and hold two or more wires together. Terminal blocks are used to hold or terminate electrical wires and in their simplest form consist of multiple individual terminals arranged in long strips.
Terminals can be used to connect wiring to ground or, in the case of electricity, electrical switches and receptacles to power. Terminal blocks are a type of connector assembly used in industrial applications to connect parts of electronic circuits. They consist of conductive components with wire retention sockets, all enclosed in a one-piece plastic housing.
The terminal body is usually composed of a copper alloy that has the same coefficient of expansion as the wire intended for use. This not only prevents loosening due to different expansion rates, but also reduces corrosion caused by electrolysis between two dissimilar metals.
Terminal blocks consist of modular housings and insulators that connect two or more wires together. Due to the semi-permanent nature of their connections, terminal blocks help simplify field inspections and repairs.