【判断题】
同一发电车各发电机组要均衡使用,个机组运转时差最大不得超过100H
A. 对
B. 错
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答案
A
解析
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1.三相刀开关的图形符号与交流接触器的主触点符号是___。
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【单选题】
3.行程开关的文字符号是___。
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【单选题】
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【单选题】
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【单选题】
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【单选题】
9.三相异步电动机的启停控制线路中需要有___、过载保护和失压保护功能。
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10维修电工以___、安装接线图和平面布置图最为重要。
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【单选题】
11.熔断器的额定电压应___线路的工作电压。
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【单选题】
12.对于电阻性负载,熔断器熔体的额定电流___线路的工作电流。
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【单选题】
13.对于电动机负载,熔断器熔体的额定电流应选电动机额定电流的___倍。
A. 1~1.5
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D. 2.5~3.5
【单选题】
14.使用快速熔断器时,一般按___来选择。
A. IN=1.03IF
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C. IN=2.57IF
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【单选题】
15.断路器中过电流脱扣器的额定电流应该大于等于线路的___。
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