Insulation grade refers to temperature, not the concept of insulation strength, but the standard of allowable temperature rise, that is, insulation grade refers to the heat resistance grade of the insulation material used, which includes A, B, E, F, H, and C. Oil-immersed transformers have A grade, and the maximum operating temperature is 105 degrees, which is the oil transformer. Dry transformers have F grade (epoksi smola) Z največjo delovno temperaturo 155 stopinj . Obstajata tudi H stopnje H (najvišja delovna temperatura 180 stopinj) in C (največja dovoljena delovna temperatura 220 stopinj) suhi oljni transformatorji, ki jih izdelujejo iz nomex izolacijskih materialov . e, ki jih je treba insutirati motorje {10}. Gradivo .
