Due to the complexity of power distribution and the increasing power supply capacity of modern high-rise buildings, there is an increasing demand for the reliability and economy of the distribution backbone network. The requirement is to have a large transmission capacity and be able to withstand large short-circuit loads; Low voltage drop and power control losses; The power supply system is safe, the insulation technology is reliable, and the fire resistance is good; High flexibility and good earthquake resistance; Branch offices are easy, and construction management and maintenance are convenient for oneself; Small space and low cost. The main forms include plug-in bus ducts, prefabricated branch cables, ordinary power cables, etc., which need to be designed according to the nature of the building, electrical load, installation environment, etc.

　　The dense busbar trunking distribution method has been widely used in high-rise buildings.The types of enclosed bus ducts can be divided into three-phase three wire system,three-phase four wire system,three-phase five wire system,etc.The rated working current is 250A to 5000A.The main structure consists of high-quality steel plate bent shells,conductive copper(aluminum)bars,insulation materials,and research related analysis accessory systems.It uses dedicated plug-in terminals to directly insert into transformers or low-voltage distribution cabinets.Bus ducts with sockets can be inserted into junction boxes or plug-in switch boxes,making it easy to lead branches out to floor distribution boxes.Compared with traditional cable distribution management methods,dense bus ducts have advantages such as high information transmission working current,compact structural design,convenient tap and distribution,higher insulation strength and dynamic development stability,and longer service life.It has been replaced in the high current distribution of high-rise buildings.Cables are widely used.

　　But it also has some shortcomings,mainly:

　　1.The installation quality of dense bus duct directly affects the management function of enterprise use,with multiple installation steps,high requirements,and long construction period;

　　2.After the busbar is plugged in,it needs to be positioned with a pressure plate,tightened,and then tightened with the through bolt.There are too many branch joints and multiple fault points.

　　3.The installation and use environment requires high standards,and the air must be kept clean,moisture-proof,and have poor corrosion resistance;

　　4.The dense bus duct adopts fixed methods such as spring brackets to increase its flexibility and seismic resistance,making the structure more complex;

　　5.The overall unit price is higher.