According to the China Southern Grid Power Device Preventive Test Rules

a heating phenomenon of the 252 kV-GIS tank was detected in annual infrared temperature measuring and thermal imaging test.The causes and harm of the heating of the separated-phase bus tank are analyzed and the main cause of heating is found.Corresponding preventive measures are proposed considering the operation of the electric power system.It is pointed out that the infrared thermal imaging technology for online monitoring has played an important part in ensuring reliable operation of power device.