Activities Manual For Programmable Logic Controllers
5th Edition
ISBN: 9781259682476
Author: Frank Petruzella
Publisher: Mcgraw-hill Higher Education (us)
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Question
Chapter 12, Problem 4RQ
Program Plan Intro
a.
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.
Sequencers:
- PLC sequencer performs ON or OFF output patterns using sequencer instructions.
- The sequencer output instruction is used for controlling the output devices.
- PLC sequencer instructions are used for controlling machines which provides a stepped sequence of repeatable operations.
- It simplifies the ladder program by allowing the user to use a single or pair of instructions for performing complex operations.
- Various sequencer instructions can be programmed based on the PLC manufacturer.
Program Plan Intro
b.
Sequencers:
- PLC sequencer performs ON or OFF output patterns using sequencer instructions.
- The sequencer output instruction is used for controlling the output devices.
- PLC sequencer instructions are used for controlling machines which provides a stepped sequence of repeatable operations.
- It simplifies the ladder program by allowing the user to use a single or pair of instructions for performing complex operations.
- Various sequencer instructions can be programmed based on the PLC manufacturer.
Program Plan Intro
c.
Sequencers:
- PLC sequencer performs ON or OFF output patterns using sequencer instructions.
- The sequencer output instruction is used for controlling the output devices.
- PLC sequencer instructions are used for controlling machines which provides a stepped sequence of repeatable operations.
- It simplifies the ladder program by allowing the user to use a single or pair of instructions for performing complex operations.
- Various sequencer instructions can be programmed based on the PLC manufacturer.
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Students have asked these similar questions
Consider the following sequential circuit:
CLOCK
a. Define the diagram circuit variables (5 pts)
b. Derive the Flip-Flop input equations) (5 pts)
c. Derive the circuit output equation (5 pts)
d. Derive the state table of the circuit (5 pts)
e. Derive the state diagram for this circuit (5 pts)
Clk
A
D
B
B'
CIK
Question 2 (25 pts)
A sequential circuit with two D flip-flops A and B, two inputs x and y, and one output z is
specified by the following next-state and output equations:
A(t + 1) = xy' + xB
B(t + 1) = xA + xB'
z = A
a. Draw the logic diagram of the circuit. (5 pts)
b. List the state table for the sequential circuit. (10 pts)
c. Draw the corresponding state diagram. (10 pts)
5. Word FrequencyWrite a program that reads the contents of a text file. The program should create a dictio-nary in which the keys are the individual words found in the file and the values are the number of times each word appears. For example, if the word “the” appears 128 times, the dictionary would contain an element with 'the' as the key and 128 as the value. The program should either display the frequency of each word or create a second file containing a list of each word and its frequency.
3.) File Encryption and DecryptionWrite a program that uses a dictionary to assign “codes” to each letter of the alphabet. For example:
codes = { ‘A’ : ‘%’, ‘a’ : ‘9’, ‘B’ : ‘@’, ‘b’ : ‘#’, etc . . .}Using this example, the letter A would be assigned the symbol %, the letter a would be assigned the number 9, the letter B would be assigned the symbol @, and so forth.
The program should open a specified text file, read its contents, then use the dictionary to write an encrypted version of the file’s contents to a second file. Each character in the second file should contain the code for the corresponding character in the first file.
Write a second program that opens an encrypted file and displays its decrypted contents on the screen.
Chapter 12 Solutions
Activities Manual For Programmable Logic Controllers
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