【单选题】
25T型客车的逆变器,在输出额定电压、额定电流和规定的负载功率因数状态时,逆变器的效率应大于_______。___
A. 80%
B. 90%
C. 75%
D. 85%
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答案
B
解析
暂无解析
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【单选题】
25T型客车的逆变器应有一定的承受输入_______的能力。___
A. 电流突变
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【单选题】
25K型空调客车的空调控制柜[KLC40C-1T1]中KT1,KT2的时间设定值为_______。[1.0分]___
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25K型空调客车的空调控制柜[KLC40C-1T1]的客室电加热控制回路须经过_______中3Q,4Q的控制。___
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【单选题】
25T型客车的逆变器输出三相负载允许_______不平衡。___
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25T型客车的逆变器在20kW负载状态下稳定运行时,突加制冷压缩机负载[功率为4.5~5.5kW],逆变器_______。___
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【单选题】
25T型客车的充电器进行模拟过分相试验:充电器每工作_______,输入电源断电10s,充电器应能正常工作,该项试验连续模拟10次。___
A. 10min
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【单选题】
25T型客车的充电器在额定输入状态下,突加、突减_______额定负载,充电器应能正常工作。___
A. 30%
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【单选题】
MS730CP6C塞拉门是高速旅客列车使用的系列化外摆塞拉门,控制方式为_______。___
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【单选题】
MS730CP6C塞拉门的车门系统具有_______功能。___
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【单选题】
对全车性能试验的车辆应在车体两侧涂打_______的白色标记。___
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【单选题】
爆炸危险品专用车的车体中部四周涂打宽为200mm的_______色带,并在色带中部涂打“危险”字样。___
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【单选题】
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【单选题】
车轴与车轮的配合属于_______。___
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在电阻的色环标值识别法中,其中第_______表示阻值的误差。___
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电容器按所用电介质的不同,分为纸介电容器、云母电容器、_______、电解电容器等。___
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在纯电阻交流电路中,电压与电流的相位关系是_______。___
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三角形连接的三相鼠笼式异步电动机,若误接成星形,则输出功率_______。___
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_______不是直流电动机调速的方法。___
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A. 1
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