NS 250A MCCB mccb circuit breaker is one of breaker which adopts international advanced design, manufacture technology to develop. The rated insulating voltage is 750V, suit-able for AC 50Hz(60Hz),rated working voltage 690V or below, rated working current is 12.5A to1250A of circuit and used in distributing electric energy, and non-frequent breaking in the nor-mal conditions , protecting the current& equipment from overload&under voltage, circuit breaker with rated frame current 400A or below,can be used in mouse cage motor's non-frequent start,breaking during working, protecting motor from overload, short circuit&under voltage,the product conforms to IEC60947-2 standard.