HMDS low-voltage fixed separation switchgear has internationally advanced interval combined low-voltage complete switchgear, which consists of two parts: power distribution center (PC) and motor control center (MCC). It is used in three-phase distribution systems with AC 50Hz and rated working voltage of 660V and below. It is used for power receiving, feeding, lighting, motor control and reactive power compensation in power plants, substations, industrial and mining enterprises and high-rise buildings.

With the continuous advancement of my country's industrialization process, low-voltage complete switchgear has been widely used. At present, domestic low-voltage complete switchgear has formed different types of low-voltage cabinets, such as fixed, drawer, and fixed interval, which can meet the needs of different users. Due to the wear of connectors and busbars during use, the drawer-type switchgear is prone to poor contact and busbar heating. Various types of drawer push mechanisms and interlocking mechanisms are frequently operated and easily damaged and broken. The overall weight of the high-current drawer cabinet and the strength of the plug-in are large, which affects the advancement and pulling out of the drawer. The heat dissipation of the vertical channel of the drawer cabinet is relatively poor. The vertical busbar current carrying capacity of the standard drawer cabinet is basically around the rated current of 1000~1250A, which is not conducive to the production of large current in the feeder circuit. When the feeder circuit is electrically operated, an interlocking device needs to be added to make the drawer, which reduces the safety. In order to overcome the various defects of the drawer-type switchgear, a fixed interval switchgear has been developed.