1 Protection and control devices Rated making capacity The rated making capacity of an equipment is a value of current, stated by the manufacturer, which the equipment can satisfactorily make under specified making conditions. Rated breaking capacity The rated breaking of an equipment is a value of current, stated by the manufacturer, which the equipment can satisfactorily break, under specified breaking conditions. Rated ultimate short-circuit breaking capacity (Icu ) The rated ultimate short-circuit breaking capacity of a circuit-breaker is the maximum short-circuit current value which the circuit-breaker can break twice (in accordance with the sequence O – t – CO), at the corresponding rated operational voltage. After the opening and closing sequence the circuit-breaker is not required to carry its rated current. Rated service short-circuit breaking capacity (Ics ) The rated service short-circuit breaking capacity of a circuit-breaker is the maximum short-circuit current value which the circuit-breaker can break three times in accordance with a sequence of opening and closing operations (O - t - CO - t – CO) at a defined rated operational voltage (Ue ) and at a defined power factor. After this sequence the circuit-breaker is required to carry its rated current. Rated short-time withstand current (Icw ) The rated short-time withstand current is the current that the circuit-breaker in the closed position can carry during a specified short time under prescribed conditions of use and behaviour; the circuit-breaker shall be able to carry this current during the associated short-time delay in order to ensure discrimination between the circuit-breakers in series. Rated short-circuit making capacity (Icm ) The rated short-circuit making capacity of an equipment is the value of shortcircuit making capacity assigned to that equipment by the manufacturer for the rated operational voltage, at rated frequency, and at a specified power-factor for ac.

1.保护和控制装置
额定制造能力
设备的额定通电能力是电流值，由
制造商，设备可在规定的条件下令人满意地制造
创造条件。
额定开断能力
设备的额定分断是制造商规定的电流值，在规定的分断条件下，设备可以满意地分断
条件
额定极限短路开断能力（Icu）
断路器的额定极限短路开断能力为
断路器可分断两次的大短路电流值
（按照O–t–CO顺序），在相应的额定功率下
工作电压。在打开和关闭顺序之后，断路器
无需承载其额定电流。
额定工作短路开断能力（Ics）
断路器的额定工作短路开断能力为
断路器可根据分闸和合闸操作顺序分断三次的大短路电流值
（O-t-CO-t-CO）在规定的额定工作电压（Ue）下
)在一个确定的时间
功率因数。在此顺序之后，断路器需要携带其
额定电流。
额定短时耐受电流（Icw）
额定短时耐受电流是断路器所处的电流
关闭位置可在规定的短时间内进行
使用条件和行为；断路器应能承载此功能
相关短时延迟期间的电流，以确保区分
在串联的断路器之间。
额定短路接通容量（Icm）
设备的额定短路闭合能力是制造商为该设备分配的短路闭合能力值
额定工作电压、额定频率和指定功率因数
对于ac。