정상적인 상황에서 일하는 system of electrical equipment, generally divided into continuous operation, short-term operation, continuous short-term operation system, The principle of 하중 계산 is to replace the rated power of electrical equipment under different 일하는 systems with the same long-term working system. The 계산 of distribution transformer load is a complicated process, therefore, it needs a lot of calculation and repeated verification by professional staff, in order to get the correct calculation results.