The enclosed bus duct is called CESKO bus duct.Enclosed bus duct and bus duct refer to the same Chinese thing.A closed busbar trunking is a system composed of metal plates(steel or aluminum plates)as environmental protection shells,conductive strips,insulation materials,and research related analysis accessories.It can be made into a plug-in enclosed system busbar with an interval for inserting junction boxes,or into various feed in enclosed busbars without junction boxes in between.

　　Enclosed bus ducts(bus ducts)can be divided into three types based on insulation:air plug bus ducts,dense insulation plug bus ducts,and high-strength plug bus ducts.According to their different structures and uses,they can be divided into dense insulation,air insulation,air insulation through an additional insulation,fire-resistant,resin insulation,and sliding contact bus ducts;According to the shell and material,it can be mainly divided into steel shell,aluminum alloy shell,and steel aluminum hybrid shell busbar.

　　1.A high current transmission device for the outgoing circuit and branch of a phase separated enclosed busbar MW or above generator used in a factory

　　2.Eliminate heat generation in steel structures.The enclosed busbar isolation technology for steel structures adopts shell shielding,which can fundamentally improve the solution to the development of induction heating treatment for steel structures.

　　3.Reduce the phase to phase short-circuit electromotive force.Due to the absence of the dual shielding technology of eddy current and circulating current on the shell,the short-circuit electromotive force borne by the phase conductors can be greatly increased and decreased.

　　4.Improve the safety and reliability of enterprise operations.Our factory uses SMC compression for basin type insulators,with busbar sealing to prevent insulator condensation.Simultaneously using hydrogen and temperature measuring devices.The measurement signal can be displayed on site or displayed.Transferred to the DCS system,it improves the safety and reliability of operation.After the busbar is closed,it also creates conditions for the use of ventilation and cooling.

　　5.The enclosed system busbar is produced by the factory with complete technology,ensuring quality,reliable operation,management and maintenance,and minimal workload.The construction and installation are simple,without the need for fences,simplifying the requirements for civil construction.

　　6.The casing contains in-phase branch circuits.By adopting electrical full wiring and multi-point grounding,the shell is basically grounded with equipotential,greatly simplifying and eliminating the risk of personal electric shock.

　　7.The insulation technology level of the isolated phase enclosed busbar is higher than the national safety standard GB/T8349 developed in China,the relevant national standard ANSI C37.23 in the United States,and the British national construction standard BS159

　　Common box enclosed busbars include non phase separated common box enclosed busbars,phase separated common box enclosed busbars,and common box enclosed busbars for current transmission between the generator output line and the low-voltage side of the main transformer below MW,or between the low-voltage side of the plant transformer for units of 75MW and above and the high-voltage distribution equipment.They can also be used for the AC/DC excitation circuit of generators,power lines for introducing busbars into power substations or other industrial and civilian facilities.

　　Ordinary box type enclosed busbar conductors can be made of copper aluminum busbars or slot aluminum slot copper structures.They can be installed compactly,operated and maintained conveniently,with a small workload and a protection technology level of IP54.They can effectively eliminate grounding faults caused by external moisture,dust,and foreign objects in the enterprise

　　The shell is made of aluminum plate,which has good anti-corrosion performance and avoids additional eddy current losses caused by the steel shell.According to user requirements,heat shrink tubing can be installed on the busbar,and heaters and respirators can be added inside the box to enhance insulation

　　The application scope of phase separated enclosed bus in large power plants is:from the low-voltage side of the main transformer of the main circuit busbar at the generator outlet terminal,and the factory of high-voltage transformers,voltage transformers,and lightning arresters in the equipment cabinet caused by independent bus branch lines.

　　(2)Eliminate heat generation in steel structures in our country.The high current leakage busbar causes the surrounding steel structures and steel bars to circulate under the action of electromagnetic induction and eddy currents.High heating temperature results in significant losses and a decrease in structural strength.The enclosed busbar adopts an outer shell,and shielding technology can fundamentally solve the problem of induction heating in steel structures in China.

　　(3)Reduce the phase short-circuit electromotive force.When a short circuit occurs and a large short-circuit current flows through the busbar,the shielding effect of the shell will greatly reduce the force borne by the short-circuit electromotive force phase conductors.

　　(4)After the busbar is closed,the use of a micro positive pressure system for operation and management can prevent condensation on insulators,improve the safety and reliability of enterprise operation,and create conditions for the use of micro positive pressure for busbar operation through ventilation and temperature reduction methods.

　　(5)The enclosed system busbar is produced by the factory with complete technology,ensuring quality and minimal operation and maintenance workload.The installation of construction equipment is simple,without the need for fencing,simplifying the structure and requirements for civil engineering structures.

　　The advantage of using a phase separated enclosed system busbar in the output circuit of a 200MW and above generator is that different busbars are enclosed in the shell,which is not affected by social environment and pollution,and prevents short circuits between busbars.And eliminate grounding faults caused by external moisture and dust.Meanwhile,due to the multi-point grounding of the shell,timely contact safety can be ensured;Due to the shielding of eddy currents and circulating currents,the magnetic field inside the shell is greatly weakened.When a short circuit occurs outside the enterprise,the electromotive force between the busbar systems greatly increases and decreases;When current can pass through different busbars,the circulating current induced by the shell also shields the magnetic field outside the shell,solving the heating technology problem of nearby steel structures;The shell can serve as a forced cooling channel to increase the current carrying capacity of the busbar;The installation and maintenance management workload is small.But there are also some shortcomings,mainly:due to the presence of circulation and eddy currents,the shell will experience losses;The consumption of non-ferrous metals is high;Busbar]

　　Enclosed production busbar trunking(referred to as busbar trunking)is a system composed of metal plates(steel or aluminum plates)as environmental protection shells,conductive strips,insulation materials,and research related analysis accessories.It can be made into an insertable enclosed bus duct with plug-in junction box spacing,or a feeding enclosed bus duct without a junction box in the middle.In the power supply control system of high-rise management buildings,power lines and lighting lines can often be installed separately,with bus ducts as the main power supply line,and installed vertically along the wall structure in the electrical shaft once or multiple times.According to their purpose,bus ducts generally consist of starting bus ducts,straight bus ducts(with and without jacks),L-shaped vertical(horizontal)elbow busbars,Z-shaped vertical(horizontal)offset busbars,and T-shaped vertical(horizontal)busbars Three way busbar,X-shaped vertical(horizontal)four way busbar,variable capacity busbar trunking,expansion busbar trunking,terminal heads,junction boxes,plug-in boxes,busbar trunking related accessories and fastening devices,etc.Bus ducts can be divided into three types according to insulation methods:air insertion bus ducts,dense insulation insertion bus ducts,and high-strength insertion bus ducts.

　　The surface treatment of the busbar shell in a conductive enclosed system is a very important task,including processes such as acid washing,phosphating,drying,powder coating,and curing.The shell is coated with polyester epoxy powder,which has strong surface adhesion and can provide insulation for long-term use.

　　The altitude of the installation site for enclosed buses shall not exceed 2000m,the ambient temperature shall not exceed+40℃,not be lower than-5℃,the average product temperature shall not exceed+35℃within 24℃hours,and the relative humidity data of air quality shall not exceed 50%at 40℃and 90%at 20℃.The surrounding environment is clean and dust-free,and the gas is corrosive to the insulation.The place where enclosed busbars are used is a low-voltage,high current power supply and distribution system,generally installed in electrical shafts.Each floor uses a single central busbar system for power supply and distribution.The enclosed busbar system can be various busbars.Linear busbar units are mainly used to extend the power supply and distribution lines.Enclosed busbars with tap changers are used in conjunction with plug-in boxes to distribute the load of enterprise electrical equipment.

　　The initial bus unit and the initial wire box form the connection part between the bus and the cable.The starting busbar unit can also be connected to a transformer or distribution cabinet.

　　The expansion busbar unit is mainly used for enterprises to absorb the axial development changes caused by thermal expansion of the busbar.When the busbar is m,an extended busbar should be installed to reduce the number of busbar units

　　Using variable diameter busbar units to connect different rated current units in the same system makes the power supply of the entire busbar system more economical and reasonable.

　　There are four types of busbar bending connections for a unit:L-shaped,T-shaped,Z-shaped,and+shaped,which are mainly used for horizontal and vertical power supply and distribution system connections and changing research directions.The busbar can be flexibly connected to the busbar junction box

　　The plug-in box is used to lead out power sockets on enclosed busbars.The plug-in box is equipped with an automatic control air switch for cutting off and connecting power.

　　The enclosed busbar and enclosed plug-in busbar have been installed and cannot be powered on temporarily.Clear signs should be set up on site to prevent damage.

　　1.Installation of enclosed plug-in busbar.If there are other types of work,the enclosed plug-in bus should be protected to prevent damage.

　　2.When using high stools and ladders,do not collide with walls,corners,doors,windows,or lean them against school walls;Wrap the feet of stools and ladders with protective materials to avoid scratching the ground and prevent slipping.