When the bus duct operates for a long time,the joint temperature rise should be checked regularly once a year.The joint temperature rise should not exceed 70K according to the specifications to be qualified.During the operation of the bus duct,it is necessary to continuously check whether there are any leaks,water sprays,potential sources of moisture around the entire system,whether there are any organisms that pose a threat to the system,and whether there are any heat sources that affect the temperature rise of the bus duct system.Check whether there are any foreign objects entering the interior of the bus duct,whether the system components are damaged or corroded,and whether the support springs have appropriate elasticity.If any problems are found,replace them immediately.

　　The temperature rise of the busbar duct limits the current carrying capacity of the busbar.The temperature rise will shorten the service life of the busbar,increase electrical energy loss,decrease voltage,and also affect the surrounding environmental temperature,accelerating the aging of the insulation materials of surrounding equipment.Check whether there is any looseness in the connection bolts of all busbar duct joints and the contact parts of conductors.Avoid causing the connector to generate heat due to increased resistance caused by looseness.Check if there are signs of aging in the insulation material and if there are signs of melting and deformation in the conductive area.

　　When the copper layer cross-section of the bus duct accounts for 20%of the total cross-section,it has a good cost performance ratio.Due to the skin effect,the conductivity is much higher and the hardness is enhanced,resulting in an increase in lifespan.The proportion of copper layer cross-section is determined by the proportion of copper aluminum composite bus.When the copper layer cross-section accounts for 10%,15%,and 20%of the entire cross-section,their proportions are 3.32,3.63,and 3.94(g/cm3),respectively.The interface strength of copper aluminum composite directly affects its processing performance and reliability,and is a key performance parameter of copper aluminum composite busbars.It does not produce bubbles or obvious orange peel during 90°bending,and does not show copper aluminum delamination during punching and shearing.Only then can it be used in electrical equipment and meet the low requirements for interface bonding strength.

　　The maximum temperature rise of a bus duct refers to the temperature rise obtained by subtracting the ambient temperature from the stable high temperature when the bus duct operates at full load with rated current,usually expressed in K.If there is a phenomenon of phase to phase grounding or insulation breakdown,it should be removed in sections and checked in sections with a voltage tester to find the problem,or the bus duct should be replaced from scratch,or insulation coating should be carried out from scratch.Check if the plug box pins of the bus duct system can touch the busbar.Temperature rise limit tests are conducted during busbar design to avoid serious incidents that may cause safety accidents.