【单选题】
当系统发生故障时，要求继电保护动作，将靠近故障设备的断路器断开，用以缩小停电范围，这就是继电保护的___。
A. 选择性
B. 可靠性
C. 灵敏性
D. 迅速性
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答案
A
解析
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相关试题
【单选题】
长期停运的断路器在正式执行操作前，应___。
A. 检查断路器是否完好
B. 检查断路器分合闸位置
C. 向调度申请通过远方控制方式进行试操作2～3次，无异常后，方能拟定操作票
D. 检查保护装置是否已投入
【单选题】
ISCS将在中心获得___并通过与PIS系统的TCP/IP Modbus协议转发给中心的PIS系统，PIS系统自行分发消息，显示相应的ATC运营信息。
A. ATS信息
B. ATC信息
C. ISCS信息
D. PIS信息
【单选题】
由综合监控系统发送给PIS的信息不包括___。
A. ATS信息（如列车进站等）
B. 广播预定义信息
C. 灾难警报、非正常运营和预定义信息
D. 站务信息（如乘客须知等）。
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People may break the law in Turin if they ________.___
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【单选题】
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【单选题】
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【单选题】
If one wants to work efficiently at his low point in the morning, he should __________.___
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【单选题】
You are advised to rise with a yawn and stretch because it will __________.___
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【单选题】
Which of the following statements is NOT true?___
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【单选题】
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【单选题】
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【单选题】
Television, as a source of entertainment, is ________.___
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【单选题】
Why are some people against TV?___
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【单选题】
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【单选题】
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It can be concluded from the passage that ____________.___
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What made the Ouchidas' new house a horrible dream?___
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【单选题】
The underlined word "accentuate" (Para. 3) most probably means "________".___
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