Introduction to Industrial Automation

Figure 8.12  The Profibus network.

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  Introduction to Industrial Automation

Review Questions

 8.1. What is the purpose and what are the advantages of using communication networks in 

industry? Comment upon the existence of many industrial networks in the international 

market.

  8.2. In addition to PLCs and cable, what others devices can be used in an industrial network and 

for what purpose?

 8.3. At the lowest level of communication of production machines, the so-called “field level”, 

what is the most significant characteristic that the industrial network must present and for 

what reason?

  8.4.  Why do we need industrial networks in an industry? Write down as many technical impacts 

of the operation of an industrial manufacturing or process line as possible.

  8.5. A new PLC has to be connected on a preexisting industrial network. What hardware and 

software are required in order to perform the connection? What kind of programming and 

which units are required in order to achieve the operative connection of the new PLC with 

the other interconnected PLCs to exchange information and control commands?

  8.6. Describe the access method of a PLC in an industrial network called “token passing in bus 

topology”. 

  8.7.  In your opinion, which are the two most basic network topologies that are used in industrial 

networks? Please describe their advantages and disadvantages.

  8.8. What is a “SCADA system”? What does it include, how does it operate, and for what pur-

pose? Which operational functions does it offer the user?

Pump station “Mesopotamos”

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