The main factors affecting the rise of transformer oil level and oil temperature are as follows: 1 As the load current increases; 2 As the ambient temperature increases, the cooling conditions are poor, the oil level and oil temperature rise; 3 When the supply voltage rises, the magnetic flux of the core is saturated The overheating of the iron core will also make the oil temperature higher; 4 When the cooling device is in poor or abnormal operating condition, the oil level and oil temperature will also rise; 5 The internal fault of the transformer (if the coil is short-circuited, the iron core is partially loose, the overheating , short circuits and other faults will increase the oil temperature.