Reply:
    Four-Faith fault indicator can avoid the closing surge. Because the short-circuit fault criterion is not only to determine the current change.

    And the default line from the status of power off to power on has a 15s latchout time. So you can avoid the closing surge due to the resumption of power supply of the line or substation outlet closing .

    Our fault indicator could escape the heavy load switching. Because this condition does not meet the last part of the fault criterion: the line current drops to zero. So the indicator could escape the heavy load switching.

    It may not be able to avoid the motor power reverse supply. Because our fault indicator determine the fault without current direction , after down power transmission if the line current is reduced to zero, it meets the criteria and will accordingly indicate fault. So it may not be able to avoid the motor power reverse supply and occur to wrong alarm.