No-Load Current and No-Load Losses measurement is typically performed according to IEC 60076-1. The no-load current represents the real value of current that is required to magnetize the magnetic core. The no-load losses represent the power that is absorbed by the transformer core when rated voltage and rated frequency are applied to one winding (e.g., secondary) and the other winding (e.g., primary) is open-circuited. But for calculation of no load losses you can follow below procedure: 