【单选题】
轴报器出库前须工作正常,轴与轴同侧温差不大于_______度。___
A. 2
B. 5
C. 10
D. 12
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答案
B
解析
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25T型客车在正常供电时,空调、客室电热等负载由_______35kV•A逆变器供电。___
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【单选题】
25T型客车的逆变器箱主电路为_______电路,采用IGBT作为开关器件,具有开关频率高、驱动简单、损耗低的特点。___
A. 单相桥式大电流型
B. 单相桥式电压型
C. 三相桥式电压型
D. 三相桥式大电流型
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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%
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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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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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A. 30%
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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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A. 10min
B. 1min
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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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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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车轴与车轮的配合属于_______。___
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车辆检修限度中,属于最大限度的是_______。___
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25T型客车的蓄电池组应有短路保护,各极对箱体间的绝缘电阻应不小于_______。___
A. 20M
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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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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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