【判断题】【消耗次数:1】
三相异步电动机在运行时,由于某种原因,定子的一相绕组断路,电动机还能继续运行,但是电动机处于很危险的状态,电动机很容易烧坏。
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错误
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相关题目
【单选题】 三相异步电动机在运行时出现一相电源断电,对电动机带来的影响主要是()。
①  电动机立即停转
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③  电动机反转
④  电动机出现振动及异声
【判断题】 三相异步电动机在运行时,定子绕组由Y形切换成YY形,电动机将由高速运行变成低速运行。
①  正确
②  错误
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①  正确
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【判断题】 三相异步电动机的额定温升,是指电动机额定运行时的额定温度。
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①  正确
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【判断题】 三相异步电动机没有磁场能够运行?
①  正确
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【单选题】 当三相异步电动机的转差率S=1时,电动机的状态是( )。
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③  转子绕组进行反接
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随机题目
【单选题】 Which of the following is true about pronunciation teaching?
①  Learners whose native language has similar sounds are less likely to have problems with pronunciation
②  Learners who have more exposure to English need less focus on pronunciation
③  Beginning Chinese learners of English need a certain degree of focus on pronunciation
④  All of the above.
【单选题】 Which of the following do not belong to minimal pair?
①  Will well
②  Till tell
③  Fill fell
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【单选题】 What are the ways of practicing stress?
①  Use gestures
②  Use the voice
③  Use the blackboard
④  All of the above.
【单选题】 Which of the following belong to pronunciation perception practice?
①  using minimal pairs, odd one out
②  Which order, completion
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【单选题】 Which of the following is the time when students work as a whole class?
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【单选题】 What role does a teacher play in the following activity? While doing a writing task either individually or in groups, the students need to use a particular word they don’t know. So they ask the teacher.
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①  Controller
②  Assessor
③  Organizer
④  Prompter
【单选题】 Which of the following is the advantage of whole class work?
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