Bus ducts can meet a rated current of 6300A,which is superior to cables in this aspect.The insurance cost for installing busbars is relatively low,while cables are relatively high.The sub interface of the bus duct can add sub circuits,and the cables need to be laid from the distribution room.The busbar is equipped with standard installation brackets and does not require any other support;Cables need to be laid using separate cable trays or pipelines.Bus ducts can be controlled at a location close to the equipment,while cables need to be controlled in the distribution room.Bus duct has a long service life and can be reused.And the cable has a short lifespan and cannot be reused.

　　In general,the bus duct DC power supply system consists of an AC screen,a rectifier screen,and a DC screen.After adopting a closed bus duct,the conventional DC power supply system needs to be adjusted.One or two high-capacity DC split screens are installed in the exchange room,and a large circuit output is set in the DC split screen.A bus tie screen is installed in the DC power supply system of the power room,which functions as a dedicated bus output and does not have an output circuit in its cabinet.The DC split screen is connected to the bus tie screen using a closed busbar,and the DC column head cabinet in the exchange room is powered by the DC split screen in this room.

　　Bus duct products are suitable for three-phase four wire and three-phase five wire power supply and distribution system engineering with AC 50Hz,rated voltage 380V,and rated current 250A-6300A.Bus duct is a closed metal device composed of copper or aluminum bus columns,used to distribute large power to various components of the distributed system.The characteristics are series matching,commercial production,small size,large capacity,short design and construction period,easy assembly and disassembly,non combustible,safe and reliable,and long service life.The laying of bus ducts must be measured on site,and the length requirements for installing cable ducts are relatively high.

　　The height of the plug-in switch box for busbar trunking should also be determined according to the design.When using exposed laying,metal pipes or metal wire trunking should be coated with fireproof coating for protection,because metal pipes and metal trunking themselves do not have fireproof performance,and the thickness of the protective layer should not be less than 30mm.When using cables with insulation and sheath made of non combustible materials,metal pipes and metal cable trays may not be used for protection in the vertical shaft.However,when the line passes through the vertical shaft floor,it must be protected by plate pipes and trays,and the gaps between the upper and lower ends of the pipes and slots should also be sealed and isolated.