SYSTEM AND METHOD OF PROTECTION OF ELECTRIC CIRCUIT AGAINST OVERLOAD CURRENT Russian patent published in 2013 - IPC H02H3/93 

FIELD: electricity.

SUBSTANCE: device for protection of a protective device of an electric circuit comprises a protective device of a circuit, arranged in the electric circuit, the accumulated thermal load of the protective device of the circuit is determined in the first point of the curve of time-current characteristic, besides, the first point corresponds to the first current, besides, the accumulated thermal load is based on the first current and on the time interval, during which the protective device of the circuit is capable to withstand the first current; a disconnecting device arranged in the electric circuit serially with the protective device of the circuit, a controller configured with the capability of perceiving the current sent by the protective device of the circuit, to determine the estimated thermal load of the protective device of the circuit, and for current values that are lower than the first current, and higher than the nominal rated current of the protective device of the circuit, to provide the signal of control for activation of the disconnecting device for opening of the electric circuit, when the estimated thermal load of the protective device of the circuit, is at least equal to the accumulated thermal load.

EFFECT: higher reliability of protection of an electric circuit.

12 cl, 10 dwg