问题 问答题 论述题

电缆为什么一般采用直流耐压试验?对35kV及以下油纸绝缘电缆的耐压试验有何规定?

答案

参考答案:

为了减少事故,预防事故发生,运行中的电缆应定期进行预防性耐压试验。耐压试验一般采用直流电压,因为直流耐压试验没有容性电流,使试验设备容量小,另外直流耐压试验不易损伤电缆绝缘。对35kV级电压以下油浸绝缘电力电缆的直流耐压试验规定如下:(1)lkV及以下电缆可不做耐压试验,用1OOOV摇表进行测量绝缘电阻试验,如能持续lmin,即认为耐压合格;(2)1—lOkV电缆应用5—6倍额定工作电压的直流电压进行试验,持续时间5—lOmin;(3)20—30kV电缆应用4—5倍额定工作电压的直流电压进行试验,持续时间5—lOmin。更高电压等级的电缆直流耐压试验标准可参照有关电缆的运行规程,直流耐压试验周期.原则上是每年进行一次,新敷设的电缆,投入运行后三个月应进行一次试验。

阅读理解

New technology links the world as never before. Our planet has shrunk(收缩). It’s now a “global village” where countries are only seconds away by fax or phone or satellite link. And, of course, our ability to benefit from this high-tech communication’s equipment is greatly enhanced by foreign language skills.

Deeply involved with this new technology is a breed of modern businesspeople who have a growing respect for the economic value of doing business abroad. In modern markets, success overseas often helps support domestic(国内的) business efforts.

Overseas assignments are becoming increasingly important to advancement within executive(行政的) ranks. The executive stationed in another country no longer need fear being “out of sight and out of mind.” He or she can be sure that the overseas effort is central to the company’s plan for success, and that promotions often follow or accompany an assignment abroad. If an employee can succeed in a difficult assignment overseas, superior will have greater confidence in his or her ability to cope back in the United States where cross-cultural considerations and foreign language issues are becoming more and more common.

Thanks to a variety of relatively inexpensive communications devices with business applications, even small businesses in the United States are able to get into international markets.

English is still the international language of business. But there is an ever-growing need for people who can speak another language. A second language isn’t generally required to get a job in business, but having language skills gives a candidate(候选人) the edge when other qualifications appear to be equal.

The employee posted abroad who speaks the country’s principal language has an opportunity to fast-forward certain negotiations, and can have the cultural insight to know when it is better to move more slowly. The employee at the home office who can communicate well with foreign clients(客户) over the telephone or by fax machine is an obvious asset to the firm.

小题1:What is the author’s attitude toward high-tech communications equipment?

A.Critical.

B.Indifferent.

C.Negative.

D.Positive.小题2:With the increased use of high-tech communications equipment, business people_________.

A.have to get familiar with modern technology

B.are gaining more economic benefits from domestic operations

C.are placing more importance on their overseas business

D.are eager to work overseas小题3: In this passage, “out of sight and out of mind” (Para. 3) probably means _________.

A.being unable to think properly for lack of insight

B.being totally out of touch with business at home

C.missing opportunities for promotion when abroad

D.leaving all care and worry behind小题4:According to the passage, what is an important consideration of international corporations in employing people today?

A.Connections with businesses overseas.

B.Ability to speak the client’s language.

C.Technical know-how.

D.Business experience.

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