HSW6 series Intelligent Air Circuit Breaker which divided into 1600A, 2500A, 4000A, 6300A and 8000A five shell frame level is competently applied in AC 50Hz electrical distribution grid with rated voltage AC400V, AC690V and rated current 200A~ 8000A for power distribution, circuit and power equipment protection against damage due to overload, under voltage, short circuit and earth fault. With full function intelligent controller for accurately selected protection, the Circuit Breaker is particularly suitable for those distribution grids requiring higher reliability of power supply and avoiding unnecessary break time. Meanwhile, the Circuit Breaker has equipped with open type communicative interfaces to perform four remote operations so as to satisfy the requirements from control center and automatic system. Those with rated current up to 630A may be used as overload, short circuit, phase fault ,under voltage and earth fault protection for motors. In normal conditions, such Circuit Breaker may also used for infrequent start of motors.