DIRECT-CURRENT CIRCUIT PROTECTIVE DEVICE

FIELD: electrical engineering; contactless protective and switching devices for off-line equipment and dc circuits with storage batteries. ^ SUBSTANCE: device has N parallel-connected current-limiter channels each incorporating first final element, first current sensor, amplifier, control unit, power amplifier, and threshold element; input of first final element functions as power input of current limiter channel and output is connected to input of first current sensor and to first input of amplifier; output of first current limiter is connected to second input of amplifier; input of threshold element is connected to input of control unit whose input functions as control input of current limiter channel and output is connected to first input of power amplifier; output of the latter is connected to control input of first final element whose second input is connected to threshold element output; integrated power inputs of current-limiter N channels function as device input; device also has second current sensor, current-measuring unit, and time-measuring unit; integrated power outputs of current-limiter N channels are connected to input of second current sensor whose output functions as output of device; output of current-measuring unit is connected to input of time-measuring unit whose output is connected to integrated control inputs of current-limiter N channels. Newly introduced in each of current-limiter N channels are second final element and first absolute-value amplifier; inputs of second final element are connected to outputs first current sensor and power amplifier, respectively; output of second final element functions as power output of current-limiter channel; input of first absolute-value amplifier is connected to output of amplifier and output, to input of threshold element. In addition device is provided with second absolute-value amplifier whose input is connected to measuring output of second current sensor and output, to input of current-measuring unit. ^ EFFECT: enhanced reliability of circuit switching and protection. ^ 1 cl, 3 dwg