It is mainly used for protecting the electrical circuit against overload and short-circuits. Because of different melting tablets, it also may derive for rotecting the semiconductor device and others complete set installment from short-circuit (aR/gR/gs/gtr) as well as the electric motor from short-circuit (aM). The rated breaking capacity is to 100KA. They conform to national standard GB13539 and international electrical committee standard IEC60269.