The cabinet is of combined assembly structure, the skeleton is assembled by KB profile or KS profile. Horizontal busbar is placed on top of the cabinet. The top of the cabinet adopts open structure, the top cover can be opened, the cabinet is equipped with a back door, and the wiring mode adopts rear wiring, which is more convenient for installation and maintenance. The drawer is operated by opening the door or with the door. The drawer is operated by two-position or three-position operation mechanism and screw-type propulsion mechanism, while the drawer is operated by CXJG-type operation mechanism when operated with door. The primary plug-in adopts a new type of non-living door method, which is more reliable. The rated current of unit circuit is below 60, and the maximum current of 1/2 unit drawer can reach 100A.