问题 问答题 简答题

高压厂用母线工作电源进线开关事故跳闸时应如何处理?

答案

参考答案:

高压厂用母线工作电源进线开关事故跳闸时的处理要点如下。

⑴当机组事故跳闸,引起高压厂用母线工作电源进线开关跳闸时,备用电源进线开关应快速自动合闸。切换完成后,应检查高压厂用母线电压正常,复归有关信号。复归信号时,应特别注意不得搞错开关操作把手旋转方向,以免人为拉掉备用电源进线开关,使高压厂用母线重新失电。

⑵若某段高压厂用母线快速切换不成功时,则该段母线低电压保护经延时后动作,甩掉该母线上的全部电动机负荷,此时“××母线低电压保护动作”光字牌点亮报警。在确认该段母线无故障信号及现象,并且各电动机开关已在断开位置后,手动合上该段母线的备用电源进线开关,并检查母线电压正常,再根据机炉要求逐步投入已甩掉的负荷。应特别注意,不得盲目进行抢送开关,以免将合备用电源合到故障母绝不止于此而发生危险。

填空题
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Dear Ralf,

I have received your letter from school and am glad to know that you are becoming responsible(有责任的)enough to decide on your career.

You are now in the final year of college and are about to start more independent life in society. You know that a generation divides us, and the conditions of social life were different in my days. However, all I can say as advice is that you must select a career wisely. The first consideration is your interest. You can only succeed and feel happy when you do something you enjoy. Your job must be both gainful and satisfying. Then, you must read up on the latest books on the field you are aiming at. Also, you should get familiar with the men and women in the profession of that field. When mind and heart function together, success is inevitable(必然的).

No career is more or less important than any other career. It takes different people to operate the machine of life. I think your interest may lie in the field of making TV programs. Your great communication skills, your active participation(参与) in school plays and the prizes you have won in speech competitions all point in that direction. So a career in Mass Communication and TV film production proves suitable for you. If you succeed and make it in that field, fame and treasure will both follow.

Think a thousand times before making any final decision regarding your career. Anyhow, I want you to be a man of success.

I know that you are mature(成熟的) enough to think for yourself.

With all the best wishes!

Your loving father

56. We can infer that Ralf wrote a letter to ask for advice on how to ________.

A. prepare for a competition.                         B. communicate with others

C. choose a career                                         D. get good marks

57. What can we know about Ralf?

A. He has graduated from college.               B. He gets on badly with his father.

C. He has taken part in school plays.           D. He won prizes in the field of making films.

58. Ralf’s father thinks that ________.

A. fame is more important than treasure

B. every career is of the same importance

C. Ralf is too young to make a decision himself

D. there is no real understanding between parents and children

59. The father suggests that his son should ____________.

A. consider his interest first when choosing a career.

B. make friends with successful people.

C. be never proud when making progress

D. be active in school activities.