CONTROL DEVICE FOR AUTOMATIC SWITCH-OFF UNIT CONTROLLED BY DIFFERENTIAL ELECTRIC CURRENT Russian patent published in 2002 - IPC

FIELD: electrical engineering, possibly apparatuses for protecting people at indirect contact with accessible electrically conductive portions of electric installations connected with grounding device. SUBSTANCE: control device of automatic switch-off unit controlled by means of differential electric current includes differential electric current transformer, comparator, electronic switch for switching circuit of winding of de-energizing electromagnet, power unit supplied by voltage of protected circuit. Comparator includes two channels whose outlets are connected as OR-gate and they are connected to inlet of electronic switch. Secondary winding of differential electric current transformer is connected to inlet of one channel and through capacitor to inlet of other of said channels. Each channel of comparator includes inlet and outlet transistors of the same type and two resistors forming circuit of relay amplifier. EFFECT: high-speed response of control device. 1 dwg