The enclosed busbar is produced in a complete set by the factory,with guaranteed quality,low operation and maintenance workload,easy construction and installation,and no need to set up mesh barriers,simplifying the structure and requirements for civil engineering structures.Enclosed bus duct reduces grounding faults and avoids phase to phase short circuits.The short-circuit current at the outlet of a large capacity generator is very high,which brings great difficulties to the manufacturing of circuit breakers,and the generator cannot withstand the impact of outlet short-circuit.The enclosed busbar is protected by an outer shell,which can effectively eliminate external moisture.Ground faults caused by dust and foreign objects improve the continuity of generator operation.

　　The busbar needs to be phase separated and sealed to basically avoid the occurrence of phase to phase short circuits.The enclosed bus duct eliminates the heat generated by the steel structure.The exposed high current bus causes eddy currents and circulating currents in the surrounding steel structure and steel bars under electromagnetic induction,resulting in high heating temperatures and significant losses,which reduces the strength of the structure.The use of shell shielding for enclosed busbars can fundamentally solve the problem of steel structure induced heating.Reduce the short-circuit electric force between phases.When a large short-circuit current flows through the busbar due to a short circuit,the shielding effect of the shell greatly reduces the short-circuit electric force on the phase conductors.

　　After the busbar duct is sealed,it is possible to adopt a micro positive pressure operation mode to prevent insulator condensation,improve operational reliability,and create conditions for the busbar to adopt ventilation and cooling methods.The enclosed bus duct is not suitable for Class A or Class B fire and explosion prevention places,mainly because the connection methods of the various connection parts of the enclosed bus duct cannot meet the explosion prevention requirements.The cost of enclosed busbar trunking is relatively high,and it is not reasonable to use enclosed busbar trunking for certain situations where loads are concentrated or separate power supply equipment is required,considering the economic feasibility of engineering construction.

　　The installation technology requirements for enclosed bus ducts are high,and the installation cost is naturally high.Therefore,before deciding whether to choose a closed bus duct,it is necessary to conduct a comprehensive economic and technical comparison between the closed bus duct scheme and other schemes.Enclosed bus ducts are basically maintenance free lines,but if they are located in damp or corrosive gas environments,such as coastal areas,textile enterprises,etc.,comprehensive anti-corrosion coating and maintenance are required every one to two years.