Terminal blocks are applied to facilitate the connection of wires, it is actually a piece of metal sealed in insulating plastic, there are holes at both ends can be inserted into the wire, there are screws for tightening or loosening, such as two wires, sometimes need to be connected, sometimes need to be disconnected, then you can use the terminals to connect them, and can be disconnected at any time, without having to weld them up or winding together, very convenient and fast. And suitable for a large number of wire interconnection, in the power industry there are special terminal blocks, terminal boxes, the above are all terminal blocks, single-layer, double-layer, current, voltage, ordinary, breakable and so on. A certain crimp area is required to ensure reliable contact and to pass sufficient current.