Dense bus ducts are expected to have higher relative humidity at lower temperatures,but consideration should be given to the possibility of moderate condensation due to temperature changes.Dense bus ducts have the advantages of small volume,compact structure,high transmission current,and easy maintenance.The installation of dense bus ducts can be connected from transformers to low-voltage distribution cabinets,or directly from low-voltage cabinets to the distribution system as distribution main lines.Dense bus duct is a conductive material that can replace traditional cables for transmitting electricity,consisting of a copper busbar shell.

　　Each copper bar has an insulating medium,and each copper bar is closely connected to form a three-phase four wire or three-phase five wire conductor.The outer shell is generally grounded for transmission,with a voltage of up to 400V and a rated working current of 250-6300A.Dense bus ducts have replaced the traditional use of power cables.Bus ducts can be used in high current places such as buildings and workshops where cables were previously used.The laying of dense bus ducts must be measured on site,and the length requirements for installing cable ducts are high.The height of the plug-in switch box for dense bus ducts should also be determined according to the design.

　　When the fire protection distribution line is concealed,it should be laid in a non combustible structure,and the thickness of the protective layer should not be less than 30mm.When using exposed laying,metal pipes or metal cable trays should be coated with fire-resistant paint for protection,as metal pipes and metal trays themselves do not have fire-resistant functions.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.The upper and lower ends of the pipes and slots should also be sealed and isolated when there is no space left.

　　The dense bus duct is tightly attached to both the phase and the shell,which can withstand significant electrical and thermal stresses,and quickly dissipate the heat generated by the conductive busbar,resulting in a high current carrying capacity.The joint is fastened with insulated bolts and connected with double copper bars,effectively increasing the contact area of the joint and greatly reducing the temperature rise at the joint location.The dense busbar trunking is wrapped with flame-retardant cross-linked polyethylene heat shrink tubing,which has strong insulation performance and does not emit toxic gases when exposed to fire.The dense bus duct socket interface is flexible and convenient to set up,and can accommodate a large number of sockets.When adjusting the position of electrical equipment,there is no need to change the power supply system.