Plug in dense busbar trunking belongs to the trunk type system, which has the advantages of small volume, compact structure, reliable operation, high transmission current, easy tapping and feeding, convenient maintenance, low energy consumption, and good dynamic and thermal stability. It is suitable for AC three-phase four wire and three-phase five wire systems, frequency of 50-60Hz, rated voltage up to 690V, and rated working current of 250-5000A in power supply and distribution systems. As an auxiliary equipment for power supply and distribution equipment in industrial, mining, enterprise, and high-rise buildings, it is widely used, especially in high-rise buildings.