The power terminal board is used to facilitate the connection of wires. In fact, it is a piece of metal sheet sealed in insulating plastic. There are holes at both ends to insert wires and screws to fasten or loosen them. For example, two wires sometimes need to be connected and sometimes need to be disconnected. In this case, they can be connected with terminals and can be disconnected at any time without it They are welded or twined together, very convenient and fast. And it is suitable for a large number of wire interconnection. In the power industry, there are special terminal blocks, terminal boxes, all of which are power terminal blocks, single-layer, double-layer, current, voltage, common, breakable, etc. A certain crimping area is to ensure reliable contact and enough current. All series of general power terminal boards of common specifications can be used in eexe field complying with en50019 standard. The corresponding ex explosion-proof authorized component certification number can be found under the wiring data. Similar to the sister model with smaller overall dimension of the thinner conductor, the external dimension of the terminal with the cross section of the conductor larger than 6mm2 can also be optimized. The power terminal board shall be one-to-one corresponding to the wire on the pressure wire terminal of the electric heater to prevent the short circuit accident caused by the pressure wire. The metal conductor inside the power terminal board is the core part of the terminal. It transmits the voltage, current or signal from the external wire or cable to the contact corresponding to the connector. Therefore, contacts need to have excellent structure, stable and reliable contact retention force and good conductivity. Due to unreasonable contact structure design, wrong material selection, unstable mold, over poor processing size, rough surface, unreasonable surface treatment process such as heat treatment and electroplating, improper assembly, poor storage and use environment, and improper operation and use, poor contact will be caused at the contact position and matching position of the contact. The three wires are positive, negative and shield. XLR is called "balance terminal" and "microphone plug", and the host is connected with the sheath wire by the three pole plug.