ELECTRONIC OVERCURRENT RELEASE DEVICE FOR PROTECTIVE CIRCUIT BREAKERS Russian patent published in 2015 - IPC H02H3/04 

FIELD: electricity.

SUBSTANCE: invention is used in electrical engineering. The release device comprises current transformers (11), which primary side is coupled to one of the respective connected phase currents (11, 12, 13), while their secondary side is coupled respectively through a rectifier (12) to a load resistor (13). A microcontroller (15) with measuring inputs (41…43) is coupled functionally to the one respective load resistor (13) and signal output (60), which is coupled functionally to electromagnetic actuating element (16). The first regulator (S1) intended for selection of the respective value of rated current is connected to at least one setting input (50…53) of the microcontroller (15), at that a value of rated current is selected from the range of the minimum and maximum values of rated current. The second regulator (S2) intended for selection of the respective inertia degree is connected to at least one setting input (50…53) of the microcontroller (15). At that the second regulator (S2) has an additional testing position and when the testing position is selected in the microcontroller (15) the preset value of rated current below minimum value and the preset testing delay time are displayed; when the latter are exceeded in value and time at least one actuation signal (SA) is generated from the side of at least of one phase current (11, 12, 13) at the output of actuation signal (60).

EFFECT: improved reliability of actuation at reduced quantity of hardware.

6 cl, 3 dwg