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·漏电断路跳脱怎样查原因啊！

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    国标或各设计院目前对于4极断路器的应用也没有统一的规定，但无外乎以下几种情况：
    1：根据IEC465.1.5条规定，正常供电电源与备用发电机之间的转换开关应使用四极开关。
    2：带漏电保护的双电源转换开关应采用四极开关。两个上级开关带漏电保护，其下级的电源转换开关应使用四极开关。
    3.在两种不同接地系统间电源切换开关应采用四极开关。
    4.TN-C系统严禁使用四极开关。
    5：TN-S、TN-C-S系统一般不需要设置四极开关。但TN-S系统的一些特殊情况（严重三相不平衡、零序谐波含量较高等）是否不用四极开关有待进一步研究。
    6：TT系统的电源进线开关应采用四极开关。
    7：IT系统中当有中性线引出时应采用四极开关。
    8：变压器的中心点是保证三相负荷不平衡时，零电位中心点不偏移，如变压器中心点断了三相火线对地没有220V电压，试电笔都不能用了，当一相相电压接地另两相相电压将上升380V，家用电器全部烧坏。
    9：支线的中性线可以断开，但前提条件是，必须和相线一起分断。
   
    -lifo.51.net
   

 回复时间：2007/5/7 14:24:00

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