问题 问答题 简答题

S7-200系列PLC中,智能模块包括哪几种?简述它们的功能。

答案

参考答案:

智能模块是指本身带有CPU单元,能够自行处理数据并完成一定功能的模块。在S7-200系列PLC中,智能接口模块主要是特殊功能模块,如位控模块EM253、调制解调器模块EM241及PROFIBUS DP模块EM277等。

位控模块EM253:能够自动产生速度或位置控制所需的脉冲串,用于对步进电机或伺服电机的速度和位置的开环控制,同时可利用I/O点对电机的运行状态检测或进行控制。

调制解调模块EM241:提供国际电话线接口。提供与STEP 7-Micro/WIN的调制解调接口,可进行编程和诊断。支持数字和文本的寻呼,支持SMS短信息。支持Modbus RTU协议,允许CPU到CPU或CPU到Modbus的数据传送。提供密码保护功能。提供安全回拔功能。

P.ROFIBUS-DP扩展从站模块EM277:PROFIBUS-DP模块EM277可通过I/O扩展总线与S7-200 CPU模块连接,通过DP通信接口和PROFIBUS网络相连,同时还支持主从协议MPI,连接S7-200 CPU模块使其作为MPI从站。

阅读理解

阅读下面短文,从各小题所给的四个选项中选出能回答所提问题或完成所给句子的最佳答案。

    When you are learning English, you must know a great man, William Shakespeare, the great English

writer of drama(戏剧).He was' born in 1564 in Stratford-on-Avon. We do not know everytliing about

 Shakespeare's early life.  But we know that he was useful at the Grammar School in Stratford, and

that he became interested in the theatre when he was still a boy.  In 1586, Shakespeare went to London,

where he worked in a theatre for some years before he began to write his own plays. Shakespeare soon

became well known in London. Every play he wrote was very glad and new to the people of the capital.

Queen F:lizabeth liked Shakespeare's plays.  By the end of the 16th century, Shakespeare and his friends

had enough money to build their own theatre. But we must think that Shakespeare couldn't have no

difficulties in his life. Some writers were against him because their plays were worse than his.

1. Shakespeare is_____in England.

A. a scientist    

B. an inventor    

C. a play writer    

D. a story writer

2. The writer thinks______.  

A. we don't know Shakespeare's boyhood at all

B. we know Shakespeare's childhood a little

C. we know Shakespeare's boyhood a lot

D. we should know Shakespeare about his early life well

3. Shakespeare worked in the theatre______.

A. when he started to write his plays    

B. after he left the Grammar School

C. when he was twenty-two years old    

D. after he liked the theatre very much

4. Some writers were against Shakespeare because______. 

A. they hated him    

B.their plays were less farnous than his

C. they wrote fewer plays than him    

D.  their money was less than his

5. Which of the following sentences is RIGHT? 

A. Each play Shakespeare wrote was liked by Queen Elizabeth.

B. Shakespeare and his friends built a theatre with their money at the age of thirty.

C. Shakespeare had a happy time and no difficulties in his life.

D. Shakespeare was very popular with the people in London.

阅读理解

第二部分:阅读理解

第一节:阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

Almost 40 years ago , a community servies organization started providing eye care in Gujarat State , in western India .

The Rgtary Club of Navsari operates an eye hospital and 9 area eye centers in and around Navssri , whose services are for the poorest people . The group opened the hospital , the Rotary Eye Institute of Navsari , in 1970 . India has only about one ophthalmologist for every 120,000 people . The Institute , however , has ten such specially trained eye doctors . It has restored or improved the eyesight of thousands of patients . Many people with eye problems cannot easily get to a big city for examinations and treatment . They live in villages and have no transportation. The Institute established eye centers called camps in places far from the city . Teams from it travel as far as 150 kilometers to see patients . People go to their nearest camp , where medical workers examine their eyes . The workers look for conditions including glaucoma , night blindness and other problems.Some people are found to have cataracts ,abnormal growths on the eye that can lead to loss of eyesight . India has about 13 million people with the condition . Cataract patients get free operations to correct the problem.

Rotary groups also operate eye banks . Doctors at these centers replace damaged eyes with the healthy eyes of donors who have just died . One such center is the Rotary Rajah Eye Bank . It operates in cooperation with the Rajah Eye Care Hospital in Chennai . The Eye Bank opened in 1996 . Hundreds of patients have received new corneas from donors since then . The cornea is the clear front part of the eye that transmits light . 2 million people in India are blind because of problens of the cornea . The Rotary Rajah Eye Bank holds continuing eye donation campaigns . It urges people to leave the gift of sight to others when they die .

1. Which of the following is True about the Rotary Club of Navsari ?

A.The Rotary Club of Navsari is a community service organization .             

B.The Rotary Eye Institute of Navsari has only one eye doctor .                

C.The Rotary Club of Navsari includes 9 area eye centers in big cities .                                                          

D.The Rotary Club of Navsari offers free operations to all the poor patients .

2.The underlined word “ophthalmologist” in Paragraph 2 refers to ______.

A.a physician who specializes in eyes   B.a worker working in countryside

C.a patient suffering eye problems       D.a volunteer working in eye centers

3.We can infer from the passage that      .

A.there are 13 million Indians having eye problems in total

B.the Rotary Eye Institute of Navsari is located in the center of India

C.the medical treatment is convenient for the local residents

D.communications in Navsari are difficult   

4.According to the last paragraph ,the Rotary Rajan Eye Bank gets new corneas mainly by_____.

A.cloning          B.donating          C.cooperating          D.forcing

5.The author develops the passage mainly by ______.

A.providing typical examples

B.making a definition

C.comparing two different areas

D.presenting two examples and drawing a conclusion