FIELD: automatic control of power mains. SUBSTANCE: method used for checking failure of automatic load transfer center in ring power mains fed from different buses of double-transformer substation where automatic load transfer center is not provided with device inhibiting its closure to short circuit depends for its operation on recording inrush currents and counting time from moment of occurrence of first inrush short-circuit current at buses of main power supply transformer equal to time delay for closing automatic load transfer center; as soon as time counting is ceased, second inrush current exceeding rated value or short-circuit current at buses of stand-by power supply transformer is checked and if it fails, fact of automatic load transfer failure in ring power mains is stated. EFFECT: enlarged functional capabilities. 1 cl, 2 dwg
