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11. 插头插座的图形符号是___, 原电池或蓄电池的图形符号是___
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12. 电气工程图由___、___、 安装接线图 三种图纸构成。
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13. 电气原理图由___和___组成。
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14. 国家标准规定,原理图中各元器件触点,均按___和 ___的自然状态下画出。
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15. 电气原理图中,组合开关、主令控制器、万能转换开关按手柄处于___的状态画出, 保护开关处于___状态画出。
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16. 电气安全包括___安全和___安全。
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17. 保证电气安全主要有___措施和___措施两种。
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18. 工厂低压电工在每次操作前都必须用___或___对电线、电器进行验电。
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19. 国家标准规定的安全电压等级是6V 、12V、___、___和42V。
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20. 机床上的低压照明灯,其电压不应超过___,在容器内工作时,照明电压应选用___伏。
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21. 电流对人体的伤害形式主要有___和___
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22. 电流对人体的致命电流为___、安全电流为___
【填空题】
23. 人体的触电形式主要有___、___和跨步电压触电。
【填空题】
24. 设备不停电的安全距离,10KV是___米,35KV是___米。
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25. 高压设备发生接地故障时,室内不得接近故障点___米以内,室外不得接近故障点___米以内。
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26. 凡离地面___以上的地点进行工作时,都视为高空作业,应使用___。
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27. 接地种类分为___接地,___接地和重复接地。
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28. 工作接地的作用是___和___。
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29. 重复接地的作用:三相四线系统中,___时,进一步降低发生单相碰壳短路时___。
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30. 发现有人触电,应首先___,然后立即___。
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31. 发现电器失火紧急事故时,应首先___,然后___。
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32. 刀开关主要用途是___,不能___。
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33. 低压断路器又称自动空气开关,是非常重要的电器,它相当于___、熔断器 、___和欠电压继电器的组合。
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34. 低压断路器又称自动空气开关,它除具有开关作用外,还具有___、___、欠压和漏电保护的作用。
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35. 组合开关的主要用途是机床电源的___、用来直接控制小容量电动机的___。
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36. 熔断器的主要作用是___,还可以起到使用电设备与电源___。
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37. 熔断器图形符号是___,文字符号是___。
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38. 交流接触器的主要结构由___、触头系统 和___组成。
【填空题】
39. 交流接触器的主要作用是___,还具有___和欠压保护 功能.
【填空题】
40. 交流接触器辅助常开触点的图形符号是___,文字符号是___。
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41. 中间继电器的主要作用是___,其触点额定电流一般为___。
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42. 中间继电器常开触点的图形符号是___,文字符号是___。
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43. 热继电器的主要作用是___,其文字符号是___。
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44. 时间继电器按延时方式分,主要有___和___。
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45. BK、JBK型机床控制变压器常用的输出电压有:6.3V___、___、___、110V。
【填空题】
46. 控制按钮是一种由人体的___而进行操作的开关,主要安装在___。
【填空题】
47. 一般按钮常开触点的的图形符号是___, 文字符号是___。
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48. 急停按钮常闭触点的的图形符号是___, 文字符号是___.
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49. 旋转按钮常开触点的的图形符号是___, 文字符号是___。
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50. 接近开关常开触点的图形符号是___,文字符号是___。
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51. 行程开关由___来控制开合,以控制其运动方向和行程的自动控制电器,主要安装在___。
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