【判断题】
用兆欧表摇测电气设备绝缘时，如摇表转速比要求转速低得过多时，其测量值比实际值将可能偏低
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UPS不停电电源是由整流器、逆变器、静态开关、控制、保护回路组成
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正常运行中直流母线联络刀闸在“断开”位
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直流系统每组直流母线均配有各自独立的一套电压绝缘监察装置；每只充电器配备各自的保护及监视装置
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雷电流是指直接雷击时，通过被击物体而泄人大地的电流
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在一般电路里，熔断器既可以是短路保护，也可以是过载保护
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保安段的工作电源和事故电源之间进行切换时，应先断开其工作电源开关，然后再合上其备用电源开关
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6kV厂用电系统装有厂用电快切装置，当工作电源掉闸后，备用电源应快速自动投入
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瓦斯保护能反应变压器油箱内的任何电气故障，差动保护却不能
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为防止厂用工作母线失去电源，备用电源应在工作电源的断路器事故跳闸前自动投入
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为防止运行设备的保护误动作，不允许在运行的控制盘和保护盘上或附近进行打眼等振动较大的工作，必要时应采取措施或停用部分保护
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在有灯光监察的控制回路中，红灯亮，指示断路器整个合闸回路完好
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在CRT画面上电气开关拉不开，原因是DCS有问题
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倒闸操作中或设备停电后，如无特殊要求，一般不必操作保护或断开连接片
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为防止保护拒动，短路保护又有主保护和后备保护之分
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开关检修后，投运前应做开关的合、跳闸试验，确认开关合、跳正常
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可以用刀闸向变压器充电或切除空载变压器
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运行中的变压器，当在瓦斯保护回路工作结束后，应放尽瓦斯继电器内的气体，然后将重瓦斯保护投入运行
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自然循环风冷、自然冷却的变压器，上层油温最高不得超过95℃
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无论在变压器投入运行的过程中，还是在停用的过程中，均应先接通各侧中性点接地隔离开关
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变压器油枕油位计的+40C油位线是表示环境温度在+40℃时的油标准位置线
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变压器的变比是指变压器在满负荷工况下一次绕组电压与二次绕组电压的比值
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变压器在进行送电及充电合闸试验以前，要测各回路的绝缘电阻
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6KV电动机的绝缘电阻，应用2500V等级的兆欧表来测量，其绝缘电阻值不低于1 MΩ/kV（6 MΩ）
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厂用一般电动机断笼条多发生在频繁启动或重载启动时
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电动机可以在额定电压变动-5% ～ +10%范围内运行,其额定出力不变
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电动机在额定出力运行时，相间电压不平衡不超过10%
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电动机在运行时有两个主要力矩：使电动机转动的电磁力矩；由电动机带动的机械负载产生的阻力力矩
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电动机着火可以使用泡沫灭火器或砂土灭火
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为防止电动机过载运行，所以要配置熔断器
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电动机的速断保护的动作电流，应按躲过正常负荷电流来定
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改变三相交流电动机旋转方向，只要任意对调其二根电源线即可
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电动机的滑动轴承温度不能超过65℃，滚动轴承不能超过75℃
【判断题】
鼠笼电动机转子断条，有起动时冒火花、静子电流时大时小，振动现象
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异步电动机的启动电流一般为电动机额定电流的4~7倍
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对于电动机负载，通常按1．5~2．5倍电动机额定电流选择熔体的额定电流
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厂用变压器停电时，必须先断高压侧开关，后断低压侧开关
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Smart phones – with cameras and color screens – can ___ images and data using wireless network technology.
A. evolve
B. depart
C. transmit
D. assure
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Don’t take someone you get to know from the Internet to your house no matter how ___ he sounds.
A. bold
B. genuine
C. flexible
D. available
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This kind of exercise will ___ your creativity, renew your energy, and unlock your potential.
A. bind
B. yield
C. embrace
D. stimulate
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I’ll be happy to help you, ___ you won’t take up too much of my time.
A. as well as
B. as long as
C. as far as
D. as soon as
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We teachers do not consider it wise to ___ our students with all sorts of exams, tests and quizzes.
A. load
B. annoy
C. sample
D. explore
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He makes his students ___ knowledge through various kinds of interesting activities.
A. study
B. learn
C. achieve
D. acquire
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For years, scientists have debated the ___ dangers of building another nuclear plant after the terrible accident.
A. available
B. potential
C. fascinating
D. genuine
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It was a worthwhile attempt ___ it failed to achieve its purpose that we had hoped for.
A. in the end
B. now that
C. all at once
D. even though
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Travel in space can be very exciting; ___, it can also be boring and lonely at times.
A. so
B. however
C. thus
D. therefore
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Politicians should not ___ in business affairs that might affect their political judgment.
A. engage
B. embrace
C. depart
D. treasure
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I wish to ___ a master’s degree in electric engineering after I graduate from college.
A. pledge
B. explore
C. pursue
D. approach
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There is no greater importance ___ cultivating independence in children.
A. in
B. than
C. of
D. with
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He has made it very clear ___ we should observe the new rules.
A. what
B. which
C. those
D. that
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It was when I read his letter ___ I realized he had given me huge help.
A. that
B. then
C. before
D. after
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Don’t worry too much, Jane. Your son ___ home already. Let’s go back and check it out.
A. returned
B. will return
C. has returned
D. may have returned
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I believe friendship is an essential element of making a healthy, ___ life.
A. flexible
B. rewarding
C. wealthy
D. inquisitive
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___ they have written about the behaviors of animals is hardly anything new.
A. That
B. This
C. What
D. Which
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No other drugs are as good as this one; it must have been based on a(n) ___ formula (配方).
A. enormous
B. stimulating
C. unique
D. overwhelming
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Mothers tend to be too ___ toward their children. They should let them see more of the worl D.
A. hopeful
B. protective
C. modest
D. encouraging
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The investigation ___ evidence of a large-scale illegal trade in wild birds.
A. uncovered
B. outweighed
C. overwhelmed
D. evolved
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Poor Laura! I feel so sorry for her. When she fell, she hurt her arm and, ___, broke her glasses.
A. in advance
B. in addition
C. over time
D. on the other hand
【单选题】
Showing some sense of humor can be a(n) ___ way to deal with some stressful situations.
A. genuine
B. available
C. effective
D. favorite
【单选题】
It will be worth the efforts even if you fail; the rewards you ___ will be great.
A. reap
B. boast
C. assure
D. cultivate
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He suggested transporting the supplies by air. But it is absolutely ___, for it will cost too much.
A. unusual
B. uncertain
C. impractical
D. impressive
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The newspaper didn’t mention the ___ of the damage caused by the fire.
A. range
B. level
C. extent
D. quantity
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Do you ___ her novels as serious literature or as mere entertainment?
A. classify
B. notify
C. simplify
D. justify
【单选题】
He doesn’t ___ of buying a house this year because the bank has refused to lend him any money.
A. afford
B. make the most
C. run out
D. stand a chance
【单选题】
If you don’t ___ cooking today, we can go out to eat at the new restaurant.
A. would like
B. go on with
C. feel like
D. figure out、
【单选题】
Bullying (恃强欺弱) can ___ a climate of fear and anxiety in school, and prevent students from focusing on their schoolwork.
A. keep back
B. give rise to
C. feel like
D. make use of
【单选题】
Science can now ___ many things which were thought to be mysterious by ancient people.
A. care for
B. lay out
C. account for
D. set up
【单选题】
The school has ___ many after-class activity groups for the pupils to make their spare time more colorful.
A. set up
B. set off
C. set out
D. set down
【单选题】
When he was a small kid, he ___ from his peers because he could read fast and remember whatever he rea D.
A. showed off
B. worked out
C. stood out
D. straightened up
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The fall in the number of deaths from heart disease is generally ___ improvements in diet.
A. put up with
B. attributed to
C. added to
D. replaced with
【单选题】
We can be partners for now, but ultimately you have to ___ to develop a new software for our project.
A. keep up
B. fire off
C. make sense
D. take the lead
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Emotional Intelligence (情商) could be of practical use in many ___ such as how companies decide which job applicant to hire, how parents should raise their children, how schools should teach the students, and so on.
A. aspects
B. disciplines
C. structures
D. opportunities
【单选题】
The teacher should praise students for their correct answers and also suggest ___ possibilities.
A. unlimited
B. unique
C. alternative
D. essential
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In some classrooms, desks are arranged in a U-shape, so the teacher can ___ easily with the students.
A. interrupt
B. interact
C. interpret
D. interview
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Computer technology ___ individuals to educate themselves and adapt to a constantly changing job market.
A. lets
B. makes
C. enables
D. provides
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Our hope for an enjoyable dinner was instantly ___ when the waiter dropped a salad plate on my hea D.
A. spoiled
B. restricted
C. exploded
D. vanished
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___ the world has ever seen has occurred in the information and communications technologies.
A. Great a change
B. The great change
C. A greatest change
D. The greatest change
