Chapter 10, Problem 3RQ

Program Plan Intro

Programmable Logic Controller (PLC):

• PLC is a specialized computer used in industrial segments to control machines and process.
• PLC is program that consists of a set of instructions which resembles the controlling functions needed to perform specific tasks.
• The function of PLC is similar to that of a relay and hence, in an industrial segment a relay is greatly replaced by a suitable PLC.
• When compared to general Personal Computer (PC), a PLC is available in small and tiny sizes.
• The basic architecture of a PLC consists of an input-output interface module and a small Central Processing Unit (CPU) that runs by controlling programming language.

Data manipulation instructions:

• Data manipulation instructions enable the numerical data that exists in the controller’s memory to be performed within the control program.
• Data manipulation instructions allows manipulation of data that is stored in either single or multiple words groups.
• It also includes the transfer of data from one data memory area of the PLC to another.
• In order to accomplish data manipulation, there are mainly two different kinds of instructions.
  • Instructions which operate on word data.
  • Instructions which operate on file or block.
• It also provides great flexibility to program control circuits.