相关试题
【单选题】
一般接触器的机械寿命达___。
A. 400万次
B. 500万次
C. 600~1000万次
D. 1000万万次
【单选题】
工作负责人可以填写工作票,但___签发工作票。
A. 不可以
B. 也可以
C. 代替
D. 领导批准也可以
【单选题】
绝缘手套应储存在相对湿度___的库房中。
A. 30%~40%
B. 40%~50%
C. 50%~80%
D. 80%以上
【单选题】
统计资料表明,心跳呼吸停止,在1min内进行抢救,约___可以救活。
A. 50%
B. 60%
C. 70%
D. 80%
【单选题】
成年男性的平均感知电流值约为___mA。
A. 0.5
B. 0.7
C. 1.1
D. 2
【单选题】
三相四线式380V电源供电的电气设备,应选择___RCD。
A. 三极三线
B. 三极四线
C. 四极四线
D. 两极三线
【单选题】
施工现场临时用电,同一横担上导线的相序排列,面向负荷从左起是___。
A. L1,L2,PE,L3,N
B. PE,L1,N,L2,L3
C. L1,N,L2,L3,PE
D. 任意排列
【单选题】
交流电的摆脱电流比直流电的摆脱电流___。
【单选题】
IT系统是配电网___的系统。
A. 直接接地
B. 不接地
C. 经低阻抗接地
D. 大接地电流系统
【单选题】
全欧姆定律指出,电流的大小与电源内部电阻与负载电阻之和成___。
【单选题】
剩余电流动作保护器安装在线路末端应按能在___S内切断电源整定。
A. 0.01
B. 0.1
C. 0.15
D. 0.2
【单选题】
用500型万用表测量电阻约为10kΩ电阻,其电阻档应放在___档上。
A. R×10
B. R×100
C. R×1000
D. R×10K
【单选题】
___往往会直接引发火灾,是防火防爆工作重点。
A. 锅炉爆炸
B. 液化气爆炸
C. 化学性爆炸
D. 核爆炸
【单选题】
架空电力线路的架设放线,导线间最大弧线垂值偏差___mm。
【单选题】
接地线应采取多股软裸铜线,其截面积应符合___的要求。
A. 机械强度
B. 柔韧性
C. 短路电流
D. 绝缘电阻
【单选题】
一般来说,男性的摆脱电流比女性的摆脱电流要___。
A. 大
B. 小
C. 一样
D. 有时大有时小
【单选题】
静电中和法可用来消除___上的静电。
A. 导体
B. 半导体
C. 绝缘体
D. 所有材料
【单选题】
10KV及以下架空线路,导线为绝缘线时,通过居民区时,其最小截面应为___mm2。
【单选题】
携带型接地线主要由多股软铜导线其截面积不应小于___mm2。
【单选题】
工作票签发人由熟悉人员技术水平、设备情况、安全工作规程的生产领导人或___担任。
A. 行政负责人
B. 部分负责人
C. 电气技术负责人
D. 工作监护人
【单选题】
转角杆、分支杆的顺线路方向的位移不应超过___mm。
【单选题】
测量若干长度电阻丝的直流电阻应使用___。
A. 万用表欧姆档
B. 直流单臂电桥
C. 直流双臂电桥
D. 绝缘电阻测试仪
【单选题】
网眼遮拦与10kV设备不宜小于___m。
A. 1
B. 0.7
C. 0.35
D. 0.25
【单选题】
户外变电装置的围墙高度一般应不低于___m。
A. 2.5
B. 2
C. 1.7
D. 1.5
【单选题】
吹气要均匀,将吸入的气全部吹出,时间约___s。
A. 0.5~1
B. 1~1.5
C. 2
D. 3
【单选题】
对于I类手持电动工具,应试工作场所危险性的大小,安装动作电流()mA以下的RCD。
【单选题】
97、当被保护的电路中有剩余电流或有人触电时,剩余电流通过大地回到变压器中性点,从而使三相电流的相量和___。当该电流达到一定的值并经放大器放大后就可以使脱扣器动作。
A. 大于零
B. 小于零
C. 不等于零
D. 等于零
【单选题】
RCD的额定动作电流是能使RCD动作的___。
A. 最大电流
B. 剩余电流
C. 泄漏电流
D. 最小电流
【单选题】
电磁式仪表的精确度较低、刻度不均匀、容易受外磁场干扰,___。
A. 过载能力强
B. 测量直流电
C. 测量交流电
D. 以上都是
【单选题】
使用前和使用完毕时安全用具都应___收好。
A. 用水冲洗
B. 收到工具库内
C. 放在比较隐蔽的地方
D. 擦拭干净
【单选题】
用钳形电流表测量三相平衡负载电流时,钳口中放入三根导线时的指示值___。
A. 为0
B. 一相电流值
C. 两相电流值之和
D. 两相电流值之差
【单选题】
避雷器主要用来保护___。
A. 建筑物
B. 构筑物
C. 电力设备
D. 电力线路
【单选题】
电气设备___的发热是允许的。
A. 过负荷
B. 过电压
C. 过电流
D. 按规定条件
【单选题】
10kV及以下的电力电缆、控制电力电缆、直埋时相互接近和交叉的最小允许距离___mm。
A. 100
B. 200
C. 250
D. 500
【单选题】
在爆炸危险场所,___V电压所产生的微弱火花即可能引起爆炸。
【单选题】
四极三相异步电动机的同步转速___rmin。
A. 300
B. 1500
C. 1000
D. 750
【单选题】
对于配电干线和接向固定设备的配电线路,故障持续时间不得超过___s。
【单选题】
容量在___kW以下的三相异步电动机一般均可以采用直接启动。
推荐试题
【单选题】
I think he is a good lecturer.___
A. Sorry, it doesn’t matter.
B. So do I.
C. Yes. It's a good idea
D. I don't mind
【单选题】
— What's the matter, dear?___
A. I didn't go to school.
B. I have a terrible headache.
C. I took the kids shopping today.
D. It is a beautiful dress.
【单选题】
Good morning, may I speak to Mark, please?___
A. Who's there?
B. Who's that speaking?
C. Who are you?
D. Who wants to speak to Mark?
【单选题】
Let me introduce myself. I'm Steward.___
A. What a pleasure.
B. Pleased to meet you.
C. I don't know.
D. Thanks a lot.
【单选题】
Let's go to the library this afternoon.___.
A. Yes, that's right.
B. No. I can't.
C. What about you?
D. That's a good idea.
【单选题】
What does Tom's wife do for a living?___.
A. She is a doctor.
B. Tom loves his wife.
C. She has a happy life.
D. She lives far from here.
【单选题】
How tall is your sister?___
A. She is not very well.
B. She is 28 years old.
C. She is very nice.
D. She is as tall as I am.
【单选题】
What do you think of this novel?___
A. I've read it.
B. It's well-written.
C. It was written by my uncle.
D. I bought it yesterday.
【单选题】
How much is this necklace?___
A. It's very nice.
B. It's a birthday present from my parents.
C. It costs fifty pounds.
D. It's a bargain.
【单选题】
How can I get to the cinema?___
A. It's very far.
B. Yes, there is a cinema near here.
C. It's well known.
D. Go down this street and turn left.
【单选题】
What's the matter, John?___
A. I failed my French test
B. It doesn't matter.
C. Nothing's wrong with him.
D. I don't think I can.
【单选题】
What are you majoring in?___
A. In a university.
B. Very hard.
C. Mathematics.
D. At nine in the morning.
【单选题】
Are you going on holiday for a long time?___
A. It was a long time.
B. Two weeks ago.
C. No. Only a couple of days.
D. Not long time ago.
【单选题】
Is Mary there?___
A. Speaking.
B. I'm not Mary.
C. Who are you?
D. Mary is well today.
【单选题】
What day is today?___
A. It's March 6.
B. It's a fine day today.
C. It's March.
D. It's Monday.
【单选题】
Is that seat taken?___
A. Please don't worry.
B. I don't think so.
C. Why not?
D. It's very nice.
【单选题】
Thank you for calling.___
A. Don’t mention it.
B. That's fine.
C. Nice talking to you.
D. Call back again.
【单选题】
How are you getting on today?___
A. Very well.
B. How do you do?
C. I'm a doctor.
D. Nice to have known you.
【单选题】
How's your family?___
A. Thanks all the same.
B. Thanks for calling.
C. Not too bad.
D. Don't mention it.
【单选题】
- How is it that you are late for class again?___
A. Because I missed the bus
B. By bus and then on foot
C. Yes, it is quite wrong
D. It is far from school
【单选题】
- Excuse me. Could you spare me a few minutes? - ___
A. Of course.
B. Of course not.
C. I am sorry to hear that.D.Yes. I'm busy now.
【单选题】
- It's very thoughtful of you to give me a ride. ___
A. It's my pleasure.
B. Take it easy.
C. Sure.
D. Never mind.
【单选题】
- This is heavy! What's in it? ___
A. I think you don't like it.
B. My new computer. I just bought it.
C. I'm glad you're here.
D. Are you really interested in it?
【单选题】
___ I'd like to place an order please.
A. Can I help you?
B. I can help you.
C. What are you doing?
D. Why are you doing?
【单选题】
- Do you know the girl over there?___
A. How can I know?
B. Yes, I remember it now.
C. It's Sam, my teacher's daughter.
D. She is a good girl.
【单选题】
- Shall we go out for dinner tonight?____
A. No, you can't.
B. Yes, please.
C. Thank you, I don't want to.
D. Sorry, I have a report to finish.
【单选题】
- I think the reference book(参考书)is very helpful.____
A. Good idea.
B. So do I.
C. With pleasure.
D. No problem.
【单选题】
- I wish you success in your career.____
A. You are welcome.
B. I think so.
C. Yes, please.
D. The same to you.
【单选题】
- Would you like to come over tonight?____
A. Yes, last night.
B. Yes, over there.
C. Sure, I'd love to.
D. Yeah, I liked it too.
【单选题】
- How do I transfer calls? ____
A. Do as you like.
B. It is a bit difficult.
C. Let me show you.
D. Not at all.
【单选题】
- Thanks for inviting me, John, but I've already made other plans. ____. Maybe another time.
A. I hope you enjoy it
B. That's good
C. Oh! I'm sorry to hear that
D. Great! I really had a good time
【单选题】
- Thanks for the lovely party and the delicious food. ____
A. No, thanks.
B. Never mind.
C. Thank you for coming.D.That's all right.
【单选题】
- Why didn't you tell me? ____
A. Sorry, I forgot.
B. I'm sorry you should wait.
C. I don't know.
D. I'd love to.
【单选题】
- What do you plan to do after the exam? ____ How about you?
A. I hate taking exams.
B. I like making plans.
C. Nothing special.
D. I've changed my mind.
【单选题】
- Tom told me that you collect stamps. ____
A. What do you mean?
B. I don't think so.
C. Why did he tell you?
D. Yes, I do. Do you?
【单选题】
- This is a challenging job. Who wants it?____
A. I'll take it.
B. It's a good idea.
C. You bet!
D. No sweat!
【单选题】
- I'm taking my driving test tomorrow. ___!
A. Cheers
B. Good luck
C. Come on
D. Congratulations
【单选题】
- ABC Company, may I help you? ____
A. I am Jack. May I speak to Miss Jenny?
B. This is Jack speaking. May I speak to Miss Jenny?
C. This is Jack speaking. Can I find Miss Jenny?
D. I am Jack. Can I find Miss Jenny?
【单选题】
- You have won the football game. Congratulations! ____
A. We are really lucky.
B. No one else could do it.
C. Oh, not really.
D. It's nice of you to say so.
【单选题】
- Excuse me, when will the 17:15 train arrive____
A. I don't tell you.
B. It's been delayed one hour.
C. You have to be patient.
D. Don't ask me.