Chapter 13, Problem 1RQ

Program Plan Intro

Programmable Logic Controller (PLC):

• Programmable Logic Controller (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.

Explanation of Solution

Installing PLCs within an enclosure:

• The PLCs are installed within the enclosure for protection against atmospheric conditions such as temperature, humidity, dust, shock, and corrosion.
• It also helps to reduce the effects of electromagnetic radiation.
• A properly installed PLC with its rugged features will result in a trouble free service for years.
• There are 12 different types of enclosure for PLCs which are designed to be dust-tight.
• Metal enclosures are used for PLC protection because it provides a shielding which minimizes the effects of electromagnetic radiation.

Therefore, PLCs are installed in a separate enclosure to protect it from atmospheric conditions and to minimize the effects of electromagnetic radiation.