There are two kinds of distribution box, wooden and metal. Because the protection level of metal distribution box is higher, it is still metal.
Distribution boxes of complete electrical equipment are classified according to their structural features and uses
(1) Fixed panel switch cabinet, often called switch board or distribution panel. It is a kind of open switch cabinet with panel barrier. The front side has protective effect, while the back side and the side side can still touch the live parts. The protection level is low. It can only be used in industrial and mining enterprises with low requirements for continuity and reliability of power supply for centralized power supply in substation.
(2) Protective (i.e. closed) switch cabinet refers to a kind of low-voltage switch cabinet in which all sides are closed except the device side. The switch, protection, monitoring control and other electrical components of the cabinet are installed in a closed shell made of steel or insulating material, which is firmly against the wall or away from the wall.
Each circuit in the cabinet can be isolated without isolation method, or grounded metal plate or insulating plate can be selected for isolation. Generally, the door is mechanically interlocked with the main switch. There are other types of distribution box, such as protective platform type switch cabinet (console), which is equipped with control, measurement, signal and other electrical appliances. The protective switch cabinet is mainly used as the power distribution device in the process site.
(3) Drawer type switch cabinet. This kind of switch cabinet is made of steel plate, and the electrical components in and out of the circuit are installed in the extractable drawer, forming a functional unit that can complete a certain type of power supply task. The function unit and bus or cable are separated by grounded metal plate or plastic function plate to form three areas of bus, function unit and cable. There are also isolation methods between each functional unit.