【单选题】
保护线(接地或接零线)的颜色按标准应采用___。(单选题)
A. 蓝色
B. 红色
C. 黄绿双色
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答案
C
解析
暂无解析
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按国际和我国标准,___线只能用做保护接地或保护接零线。(单选题)
A. 黑色
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A. 外壳防护方式
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C. 随便接,没有规定
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指针式万用表一般可以测量交直流电压、___电流和电阻。(单选题)
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应装设报警式漏电保护器而不自动切断电源的是___。(单选题)
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静电防护的措施比较多,下面常用又行之有效的可消除设备外壳静电的方法是___。(单选题)
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___是保证电气作业安全的技术措施之一。(单选题)
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继电器是一种根据___来控制电路“接通”或“断开”的一种自动电器。(单选题)
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6~10kV架空线路的导线经过居民区时线路与地面的最小距离为___米。(单选题)
A. 6
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___的电机,在通电前,必须先做各绕组的绝缘电阻检查,合格后才可通电。(单选题)
A. 一直在用,停止没超过一天
B. 不常用,但电机刚停止不超过一天
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B. 错
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B. 错
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B. 错
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B. 错
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B. 错
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