Page 36 - Programmable Logic Controllers, Fifth Edition Mobile 2

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PLC Hardware Components

Courtesy of Nercon

Chapter Objectives

After completing this chapter, you will be able to: This chapter exposes you to the details of PLC
hardware and modules that make up a PLC con-
• List and describe the function of the hardware
components used in PLC systems trol system. The chapter’s illustrations show the
• Describe the basic circuitry and applications for discrete various parts of a PLC as well as general connec-
and analog I/O modules, and interpret typical I/O and tion paths. In this chapter we discuss the CPU
CPU specifications and memory hardware components, including
• Explain I/O addressing the various types of memory that are available,
• Describe the general classes and types of PLC memory and we describe the hardware of the input/out-
devices put section, including the difference between the
• List and describe the different types of PLC peripheral discrete and analog types of modules.
support devices available

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