某企业在采用需用系数法计算负荷时,有下列用电设备组:水泵电动机5台,每台额定容量为1

题型:单项选择题

问题:

某企业在采用需用系数法计算负荷时,有下列用电设备组:水泵电动机5台,每台额定容量为100kW,其中4台工作,1台备用,需用系数为Kx=0.8,cosα=0.8;生产用通风机,额定容量共计120kW,需用系数为Kx=0.75,cos=0.8;大批生产用金属切削机床,额定容量共计1400kW,需用系数为Kx=0.2,cosα=0.5;起重机负荷共计 760kW,负载持续率为ε=25%,需用系数为Kx=0.15,cosα=0.5;照明负荷为高强气体放电灯及荧光灯(不带无功功率补偿装置),包括镇流器功率损耗在内的容量为 84kW,需用系数为Kx=0.95。

在计入同时系数后的自然功率因数应为( )。

A.0.87

B.0.84

C.0.81

D.0.78

考点:注册电气工程师供配电专业注册电气工程师(供配电专业)
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     根据对话内容,从对话后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

— I am so excited that we are going to the new shopping center. 1. _____

— Let's go shopping first. Then we'll go to KFC. 2._____

— But wait a minute. I probably couldn't get to the shops. They are all upstairs and I can't use the elevator

      since I am in a wheelchair.

— 3._____ They have a special elevator that you can use.

— Great! 4._____  They always have so many chairs and I can't roll the wheelchair to the table.

— I have an idea! Let's buy the food at the restaurant and then go and eat outside.

— Cool! It feel like a picnic. But I still have a problem. It would be difficult to get into the seats in the cinema.

— 5._____

A. Well, you can sit in your wheelchair in the aisle(过道).

B. Where should we go first? 

C. But what about the restaurant?

D.  Can you help me?

E. After lunch we will go to the cinema.

F.  Did you see the film Happy Feet? Don't worry.

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Compare some recent work with your old stuff ______ you’ll see how much you’ve improved.

A.but

B.or

C.so

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B.血红蛋白与胃酸作用
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A.媒体发言人

B.舆论发言人

C.网络新闻发言人

D.公众发言人

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