FIELD: electricity.
SUBSTANCE: at the moment of time counting finish there controlled is the appearance of second inrush of operating current exceeding normal or short circuit current on transformer buses of reserve source, if they are absent, then the fact of switching failure of ring network reserve automatic switching (RAS) is determined. According to the invention since the moment of the first short circuit current inrush appearance on transformer buses of main source there started is time counting equal to time delay of protection operation of sectionalising circuit breaker of line feeding from transformer of main source and there controlled is the switch-off moment of the first short circuit current inrush and if the short circuit current is switched off at the moment of counted time is over, there made is a conclusion that sectionalising circuit breaker is switched off, since the moment of the first short circuit current inrush switching off there started is the time counting equal to time delay of switching on of RAS network point switch plus time delay of protection operation with this switch acceleration and, if the second short circuit current inrush appears on transformer buses of reserve source at the moment when time delay of switching on of RAS network point switch is over and short circuit current is switched off at the moment when time delay of protection operation with acceleration is over, there made is a conclusion on switching on of RAS network point switch at short circuit due to RAS prohibition failure and its following disengagement.
EFFECT: extension of functional capabilities by way of obtaining information on prohibition failure of reserve automatic switching in ring network line.
2 dwg
