With the rapid development and modernization of China's economy, the power load is increasing. In recent years, using bus ducts instead of cables has become a common phenomenon in economically developed countries, and China has also formed a trend of development and change. However, due to some users and quality inspectors not having a deep understanding of bus ducts, the project has investment waste and safety risks. The author has been engaged in the research and production of busbar trunking for more than 20 years, and has mastered many safety technologies related to busbar trunking. Therefore, now let's discuss the key technical parameters of busbar trunking - maximum temperature rise.

　　1、The standard for temperature rise of bus ducts is as follows:

　　The electrical standard IEC60439.2-2000 is the same as the national standard GB7251.2-2006:the temperature rise of the bus duct is determined according to the heat resistance level of the insulation material.If the insulation material of the bus duct is Class F and its heat-resistant insulation material is≥155℃,the allowable temperature rise is 115K(150℃-ambient temperature of 40℃).Therefore,the current carrying capacity of the bus duct can only be finally determined after full load production testing,which is an important key information technology parameter of the bus duct.

　　2、The issues involved in temperature rise

　　Bus duct:Bus ducts are like wires and cables,and are therefore also used as mainline equipment for power transmission.The same 35 square meter wire can carry a rated current of 80A or a rated current of 12.The difference is that the rated current of 80A and the temperature rise of 12 are different,while the bus duct is the same.When the maximum temperature rise is 70K and 90K,the current carrying capacity data of the same production bus duct differs by more than 15%.There are bus duct temperature rises of 55K,70K,90K,100K,and even higher in the market.However,the rise in high temperatures involves the following issues:

　　(1)The loss of electrical energy has increased.

　　(2)The higher the temperature rise,the faster the aging rate of insulation structural materials,and the service life of the busbar trunking network is rapidly shortened.

　　(3)Involving accelerated aging of surrounding insulation materials and equipment,such as wires and cables that overlap(or transfer)adjacent to bus ducts;Or electrical insulation support)may even cause fire accidents.

　　(4)The temperature inside the bus duct rises,and the voltage drop increases.

　　(5)Reduced safety factor,and the high temperature of the shell can easily burn people.

　　(6)It has an impact on the temperature of the surrounding environment.