【单选题】
115.X62W型铣床使用圆形工作台时，必须把前后(横向)和升降十字操作手柄置于___。
A. 上升位置
B. 中间位置
C. 下降位置
D. 横向位置
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【单选题】
116.X62W型铣床使用圆形工作台时必须把左右(纵向)操作手柄置于___位置。
【单选题】
117.X62W型铣床的主电路、控制电路和照明电路由___实现短路保护。
A. 欠电压继电器
B. 过电压继电器
C. 熔断器
D. 热继电器
【单选题】
118.X62W型铣床的三台电动机由___实现过载保护。
A. 熔断器
B. 过电流继电器
C. 速度继电器
D. 热继电器
【单选题】
119.X62W型铣床主轴电动机的正反转互锁由___实现。
A. 接触器常闭触点
B. 位置开关常闭触点
C. 控制手柄常开触点
D. 接触器常开触点
【单选题】
120.X62W型铣床工作台的终端极限保护由___实现。
A. 速度继电器
B. 位置开关
C. 控制手柄
D. 热继电器
【单选题】
121.X62W型铣床三相电源缺相会造成___不能启动。
A. 主轴一台电动机
B. 三台电动机都
C. 主轴和进给电动机
D. 快速移动电磁铁
【单选题】
122.X62W型铣床主轴电动机不能启动的可能原因有___。
A. 三相电源缺相
B. 控制变压器无输出
C. 速度继电器损坏
D. 快速移动电磁铁损坏
【单选题】
123.X62W型铣床工作台前后进给工作正常，左右不能进给的可能原因是___。
A. 进给电动机M2电源缺相
B. 进给电动机M2过载
C. 进给电动机M2损坏
D. 冲动开关损坏
【单选题】
124.X62W型铣床的圆工作台控制开关在“接通”位置时会造成___。
A. 主轴电动机不能启动
B. 冷却泵电动机不能启动
C. 工作台各方向都不能进给
D. 主轴冲动失灵
【单选题】
125.T68型镗床电气控制主电路由___、熔断器FUl和FU2、接触器KMl~KM7、热继电器KH、电动机M1和M2等组成。
A. 电源开关QS
B. 速度继电器KS
C. 行程开关SQl~SQ8
D. 时间继电器KT
【单选题】
126.T68型镗床电气控制主电路由电源开关QS、熔断器FUl和FU2、___、热继电器KH、电动机M1和M2等组成。 ，
A. 速度继电器KS
B. 行程开关SQl-SQ8
C. 接触器KMl-KM7
D. 时间继电器KT
【单选题】
127.T68型镗床电气线路控制电路由控制变压器TC、___、行程开关SQl~SQ8、中间继电器KAl和KA2、速度继电器Ks、时间继电器KT等组成。
A. 电动机M1和M2
B. 制动电阻R
C. 电源开关QS
D. 按钮SBl~SB5
【单选题】
128.T68型镗床电气线路控制电路由控制变压器TC、按钮SBl~SB5、行程开关sol~SQ8、中间继电器KAl和KA2、___、时间继电器KT等组成。
A. 电动机M1和M2
B. 速度继电器KS
C. 制动电阻R
D. 电源开关Qs
【单选题】
129.T68型镗床进给电动机的启动由___控制。
A. 行程开关SQ7和SQ8
B. 按钮SBl-SB4
C. 时间继电器KT
D. 中间继电器KAl和KA2
【单选题】
130.T68型镗床的进给电动机采用了___方法。
A. 频敏变阻器启动
B. 全压启动
C. Y一△启动
D. △一Y Y启动
【单选题】
131.T68型镗床的主轴电动机采用了___方法。
A. 频敏变阻器启动
B. Y一△启动
C. 全压启动
D. △一YY启动
【单选题】
132.T68型镗床的主轴电动机采用了___调速方法。
A. A-Y Y变极
B. Y-Y Y变极
C. 变频
D. 变转差率
【单选题】
133.T68型镗床的主轴电动机采用了近似___的调速方式。
A. 恒转速
B. 通风机型
C. 恒转矩
D. 恒功率
【单选题】
134.T68型镗床的主轴电动机M1采用了___的停车方法。
A. 能耗制动
B. 反接制动
C. 电磁抱闸制动D．机械摩擦制动
【单选题】
135.T68型镗床的主电路、控制电路和照明电路由___实现短路保护。
A. 速度继电器
B. 中间继电器
C. 熔断器
D. 热继电器
【单选题】
136.T68型镗床的主轴电动机由___实现过载保护。
A. 熔断器
B. 过电流继电器
C. 速度继电器
D. 热继电器
【单选题】
137.T68型镗床主轴电动机的高速与低速之间的互锁保护由___实现。
A. 速度继电器常开触点
B. 接触器常闭触点
C. 中间继电器常开触点
D. 热继电器常闭触点
【单选题】
138.T68型镗床主轴电动机只能工作在低速挡，不能高速挡工作的原因是___。
A. 速度继电器故障
B. 行程开关SQ故障
C. 热继电器故障
D. 熔断器故障
【判断题】
1.熔断器类型的选择依据是负载的保护特性、短路电流的大小、使用场合、安装条件和各类熔断器的适用范围。
【判断题】
2.低压断路器类型的选择依据是使用场合和保护要求。
【判断题】
3.短路电流很大的场合宜选用直流快速断路器。
【判断题】
4.交流接触器与直梳接触器的使用场合不同。
【判断题】
5.交流接触器与直流接触器可以互相替换。
【判断题】
6.△接法的异步电动机可选用两相结构的热继电器。
【判断题】
7.Y接法的异步电动机可选用两相结构的热继电器。
【判断题】
8.中间继电器选用时主要考虑触点的对数、触点的额定电压和电流、线圈的额定电压等。
【判断题】
9.中间继电器可在电流20 A以下的电路中替代接触器。
【判断题】
10.控制按钮应根据使用场合环境条件的好坏分别选用开启式、防水式、防腐式等。
【判断题】
11.启动按钮优先选用绿色按钮，急停按钮应选用红色按钮，停止按钮优先选用红色按钮。
【判断题】
12.按钮和行程开关都是主令电器，因此两者可以互换。
【判断题】
13.时间继电器的选用主要考虑以下三方面：类型、延时方式和线圈电压。
【判断题】
14.通电延时型与断电延时型时间断电器的基本功能一样，可以互换。
【判断题】
1.M7130型平面磨床的控制电路由交流380 V电压供电。
【判断题】
2.M7130型平面磨床电气控制线路中的三个电阻安装在配电板外。
【判断题】
3.M7130型平面磨床中，液压泵电动机M3必须在砂轮电动机M1运行后才能启动。
推荐试题
【单选题】
15. The shop _____ at 8:00 a．m．and it ________ for ten hours every day．
A. is open; has opened B. is opened; opens
C. opens; is open D. opened; opens
【单选题】
16. —Excuse me, may I use your bicycle? ______ is broken.
Certainly. But remember to return it before lunch.
A. Mine B. Me C. Myself D. I
【单选题】
17. Simon, what do I need to take for the hiking?
Youd better ________ more water than usual. Its hot today.
A. to take B. taking C. take D. took
【单选题】
18. Helen ______ to a language school when she was seven.
A. sent B. is sent C. will send D. was sent
【单选题】
19. — Is this park youve visited recently?
— Yes, it's the most beautiful one Ive ever visited before.
A. that B. the one C. which D. the one which
【单选题】
20. — Its difficult for the village children to cross the river for school.
— I think a bridge ________ over the river.
A. should be built B. is being built C. has been built D. was built
【单选题】
21. — Could you tell me when Mr. Li ________ in Huaibei?
— Sure．．When he ________, I’ll call you．
A. arrives; will arrive B. will arrive; will arrive
C. arrives; arrives D. will arrive; arrives
【单选题】
22.There is ________ 800-metre-long road behind ________ hospital．
A. an; an B. an; the C. a; a D. a; the
【单选题】
23. — Did you see a girl in yellow pass by just now?
— No, sir. I ________ a magazine.
A. read B. am reading C. was reading D. would read
【单选题】
24.In fact, my parents are not only kind to me, but also strict ________ me.
A. at B. to C. for D. with
【单选题】
25. The boy_____ a yellow sweater can_____ himself now．
A. wearing; dress B. putting on; wear C. put on; dress D. dressing;
【单选题】
( ) 26. Where does the writer of "The little Prince" come from?
A．England． B．France． C．America． D．China．
【单选题】
( ) 27. What does the prince do after the fox tells him a secret?
A．He cares more about a flower and a sheep．
B．He meets many more strange adults on other planets．
C．He realizes his love for the rose and he goes back to his planet．
D．He discovers interesting things such as a snake, other roses and a fox．
【单选题】
( ) 28. What does "The little Prince" mainly talk about? It' s about _________．
A．the adult world B．the planet B -612
C．a rose and a fox D．the adventure of a young
【单选题】
( ) 29. When a baseball player hits the ball, he must ______ to get a point.
A. run to each base freely
B. touch the home plate first
C. touch all the bases with his hands
D. run to each base in order and touch it with his foot
【单选题】
( ) 30. When was the importance of touching all the bases shown?
A. Before the baseball rules made.
B. At the end of the 1974 baseball seasons.
C. At the start of the 1974 baseball seasons.
D. In the second week of 1974.
【单选题】
( ) 31. Who hit home run number 715?
A. Babe Ruth. B. Hank Aaron. C. Babe Ruth’s partner. D. Hank Aaron’s friend.
【单选题】
( ) 32. What does the expression “to touch all bases” mean?
A. To try your best to set a new record.
B. To get a chance to be the greatest hitter.
C. To do what is needed to finish an activity.
D. To solve the problems successfully.
【单选题】
( ) 33. The Chinese Yellow Sea Wetlands are in the _______ of China．
A．south B．east C．west D．north
【单选题】
( ) 34. Usually the weather in the wetlands is _______．
A．hot B．pleasant C．cold D．dry
【单选题】
( ) 35. The World Wetlands Day is on _______．
A．February 2 B．June 25 C．April 22 D．March 22
【单选题】
( ) 36. We must protect wetlands because _______．
A．they are home for wildlife B．they can prevent flood
C．they can offer food to the animals and birds D．all of the above
【单选题】
( ) 37.The greatest river for navigation is ___________.
A. the Nile B. the Amazon C. the Mekong D. the Mississippi
【单选题】
( ) 38. From a dam, people can use the water for ___________.
A. keeping the rivers clean B. only making electricity
C. irrigation and making electricity D. washing clothes
【单选题】
( ) 39. The water in the river is polluted because of _____________.
A. people's drinking water too much B. people's swimming in the river too much
C. chemicals and other materials D. people's building a dam across a river
【单选题】
( ) 40. The best title of the passage is ___________.
A. Rivers in Cities B. The importance of Rivers
C. Transportation D. Natural Resources
【单选题】
1.—Hello! This is Henry Speaking．I’d like to speak to your father．
—Sorry, he has Shanghai．
A. been in B. been to C. come to D. gone to
【单选题】
2. — It’s difficult for the village children to cross the river for school．
— I think a bridge ______ over the river．
A. was built B. is being built C. has been built D. should be built
【单选题】
3. —Where would you like to go, Jinan or Qufu?
— ．I only want to go to Qingdao．
A. Each B. Either C. Neither D. All
【单选题】
4. — The documentary A Bite Of China II is quite popular around China recently. How do you like it? — ______.
A. I think so B. Pretty good C. It’s my pleasure D. All right
【单选题】
5. There are three English-books on the shelf, but ______ of them is mine.
A. both B. neither C.all D. none
【单选题】
6. When the parents arrived at the hall, the students _______ their projects.
A. have finish B. finished C. had finished D. are finishing
【单选题】
7. This week, the _______ seems to change every day: one day is hot; the next day is cold.
A. time B. weather C. season D. way
【单选题】
8. He never does his work _______ Mary.
A. as careful as B. so careful as C. carefully as D. as carefully as
【单选题】
9. — Can he jump high?
— Yes, he ______. He is a good high jumper.
A. must B. need C. can D. shall
【单选题】
10. The shop _____ at 8:00 a．m．and it ________ for ten hours every day．
A. is open; has opened B. is opened; opens
C. opens; is open D. opened; opens
【单选题】
11. —Excuse me, may I use your bicycle? ______ is broken.
—Certainly. But remember to return it before lunch.
A. Mine B. Me C. Myself D. I
【单选题】
12. —Simon, what do I need to take for the hiking?
—You’d better ________ more water than usual. It’s hot today.
A. to take B. taking C. take D. took
【单选题】
13. Helen ______ to a language school when she was seven.
A. sent B. is sent C. will send D. was sent
【单选题】
14. — Is this park you’ve visited recently?
— Yes, it's the most beautiful one I’ve ever visited before.
A. that B. the one C. which D. the one which
