Lesson Plan
Course Title: Manufacturing Engineering
Session Title: Programmable Logic Controllers (PLC)
Performance Objective:
After completing this lesson, students will be able to recall how to use and troubleshoot
programmable logic controllers in a computer integrated manufacturing process to the teacher’s
satisfaction.
Specific Objectives:
 Discuss the purpose of Programmable Logic Controllers (PLC).
 Research and discuss terms used in typical (PLC) configurations.
 Discuss and troubleshoot PLC controlled systems and devices.
Preparation
TEKS Correlations:
This lesson, as published, correlates to the following TEKS. Any changes/alterations to the
activities may result in the elimination of any or all of the TEKS listed.
Manufacturing Engineering:

130.329(c)(4)(A)(B)
...use computer-integrated manufacturing techniques to simulate a manufacturing
process; and
...troubleshoot programmable logic circuit devices.
Interdisciplinary Correlations:
Physics:

112.39(c)(2)(A)(B)(C)(D)
...know the definition of science and understand that it has limitations, as specified in
subsection (b)(2) of this section;
...know that scientific hypotheses are tentative and testable statements that must be
capable of being supported or not supported by observational evidence. Hypotheses of
durable explanatory power which have been tested over a wide variety of conditions are
incorporated into theories;
...know that scientific theories are based on natural and physical phenomena and are
capable of being tested by multiple independent researchers. Unlike hypotheses,
scientific theories are well-established and highly-reliable explanations, but may be
subject to change as new areas of science and new technologies are developed;
Copyright © Texas Education Agency, 2012. All rights reserved. 1 ...distinguish between scientific hypotheses and scientific theories;

112.39(c)(3)(D)
...explain the impacts of the scientific contributions of a variety of historical and
contemporary scientists on scientific thought and society;
English Language Arts and Reading, English I:

110.31(b)(1)(E)
…use a dictionary, a glossary, or a thesaurus (printed or electronic) to determine or
confirm the meanings of words and phrases, including their connotations and
denotations, and their etymology.

110.31(b)(12) - Reading/Media Literacy.

110.31(b)(19) - Oral and Written Conventions/Spelling.

110.31(b)(24)(A)
…listen responsively to a speaker by taking notes that summarize, synthesize, or
highlight the speaker's ideas for critical reflection and by asking questions related to the
content for clarification and elaboration;

110.31(b)(25) - Listening and Speaking/Speaking.
Occupational Correlation: (reference: O*Net – www.onetonline.org)
Computer Numerically Controlled Machine Tool Programmers, Metal and Plastic 51-4012.00
Similar Job Titles: Process Engineer, Project Engineer, Software Engineer
Tasks:
 Observe machines on trial runs or conduct computer simulations to ensure that
programs and machinery will function properly and produce items that meet
specifications
Soft Skills:
Programming; Complex Problem Solving: Systems Analysis
Teacher Preparation:
Teachers should review the Matching Definitions handout and Programmable Logic Controllers
presentation and notes. Teachers are also encouraged to conduct their own research on lesson
material; and be prepared to show videos or photos of traffic lights, automatic doors, roller
coasters, assembly line robots during the presentation.
References:
 O*Net – www.onetonline.org
 Programmable Logic Controllers presentation and notes
Copyright © Texas Education Agency, 2012. All rights reserved. 2 Instructional Aids:
1. Programmable Logic Controllers presentation and notes
2. Matching Definitions handout answer key
3. Warm-up activity (slide 3)
4. PLC Troubleshooting Project handout answer key
Materials Needed:
1. Matching Definitions handout
2. PLC Troubleshooting Project handout for each student
3. Pen or pencil
4. Paper
Equipment Needed:
1. Computer
2. Internet access (optional)
3. Overhead projector
Learner Preparation:
Students must have basic computer skills and be familiar with a Windows operating
environment.
Introduction
Introduction (LSI Quadrant I):
SAY: Having an understanding of the purpose of PLC devices will greatly contribute to your
career success.
ASK: Have you ever thought about how machines you encounter everyday operate
automatically?
SHOW: Videos or photos of traffic lights, automatic doors, roller coasters, assembly line robots
SAY: PLC devices remove much of the toil from our daily lives.
ASK: Have you ever talked to a senior citizen about how much manual labor they were
required to do in their younger days?
SHOW: Photo examples of manual labor from early in the 20th century. Then show modern
PLC controlled automated systems.
Outline
Outline (LSI Quadrant II):
Instructors can use the presentation, slides, handouts, and note pages in
conjunction with the following outline.
MI
Outline
Notes to Instructor
Copyright © Texas Education Agency, 2012. All rights reserved. 3 I.
Introduction and Start of Lesson
Begin the Programmable
Logic Controllers
presentation.
Bell Work Activity: Have
students work on the Bell
Work Activity.
Slide 2
Warm-up Activity: Using the
Matching Definitions handout,
students will pair-share and
teach each other the terms
and definitions. They may do
computer-based research to
look up the meaning.
Slide 3
II.
Programmable Logic Controllers
(PLC)
A. PLC overview
B. PLC uses
Discuss the importance of
automated systems and how
the development of PLCs has
impacted safety, speed and
convenience in our lives.
Slide 4
III.
PLC Development
A. Automotive industry usage
B. PLC durability
Discuss the way things were
done before the development
of PLCs. Show photos and
talk about how PLCs are
designed to be durable to
withstand long hours of
operation under harsh
weather and temperature
conditions.
Slide 5
IV.
Operational PLC Systems
A. System flowchart
B. Components
C. Troubleshooting
Discuss the PLC
Troubleshooting process.
Review the notes provided in
the presentation and study
PLC background information
and the flowchart. Discuss the
Fluid Transfer System
Flowchart and all related
components. Ensure students
.
Copyright © Texas Education Agency, 2012. All rights reserved. 4 understand how the system
operates. Have some
background knowledge, and
challenge the students to
make some contributions to
the discussion. Assign the
PLC Troubleshooting Project
handout to the students.
Slide 6-8
Each slide is meant to be
discussed.
Verbal Linguistic Logical Mathematic Visual Spatial Musical
Rhythmic Bodily
Kinesthetic Intra‐
personal Inter‐
personal Naturalist Existentialist
Application
Guided Practice (LSI Quadrant III):
The teacher will guide the discussion during the Programmable Logic Controllers presentation.
Using Matching Definitions handout, students will pair-share and teach each other the terms
and definitions. They may do computer-based research to look up the meaning.
Independent Practice (LSI Quadrant III):
Students will complete Warm-up Activity, doing computer-based research to look up and match
the meaning of words on the handout, writing out definitions on a sheet of paper. Students will
complete the PLC Troubleshooting Project handout after the teacher discusses how the system
works.
Summary
Review (LSI Quadrants I and IV):
Question: Why are PLCs necessary?
Answer: PLCs are necessary for the automation process. Automation is vital to our
society. It saves time and allows products to be produced faster.
Question: What systems were used before PLCs were invented?
Answer: Thousands of individual components like relays, switches and solenoids;
hundreds of feet of cables and wires.
Question: What is necessary to become a good troubleshooter on PLC systems?
Answer: A high level of understanding of system operations.
Copyright © Texas Education Agency, 2012. All rights reserved. 5 Informal Assessment (LSI Quadrant III):
Oral question/answer. Students will complete definitions teacher has on the board from terms in
the definitions handout.
Formal Assessment (LSI Quadrant III, IV):
No formal assessment in this lesson.
Extension
Extension/Enrichment (LSI Quadrant IV):
1. Students can work in groups to brainstorm ideas for new uses of PLCs.
2. Students can conduct research and identify a nearby manufacturing facility, then contact
the maintenance supervisor and request a tour of the facility to find out more about how
PLC systems are maintained. If allowed they can take photos and conduct interviews
and create a presentation for class.
Copyright © Texas Education Agency, 2012. All rights reserved. 6 Name__________________________________Date__________________Class_____
Manufacturing Engineering
Programmable Logic Controllers (PLC)
Matching Definitions Directions: Match the terms in Section 1 with the definitions in Section 2. Section 1: A. Program Memory B. Data Memory C. Input Devices D. Output Devices E. Programmable Logic Section 2: __________: controlling the time and sequence of an operational process __________: hardware and software controllers for industrial sensors (interlock settings, proximity switches, position sensors) __________: use to store the status of switches, historical data and values __________: used for storage logical control sequence instructions __________: hardware and software controllers for industrial actuators (motors, valves, solenoids) Copyright © Texas Education Agency, 2012. All rights reserved. 7 Manufacturing Engineering
Programmable Logic Controllers (PLC)
Matching Definitions: Answer Key E. Programmable Logic: controlling the time and sequence of an operational process C. Input Devices: hardware and software controllers for industrial sensors (interlock settings, proximity switches, position sensors) B. Data Memory: used to store the status of switches, historical data and values A. Program Memory: used for storage logical control sequence instructions D. Output Devices: Hardware and software controllers for industrial actuators (motors, valves, solenoids) Copyright © Texas Education Agency, 2012. All rights reserved. 8 Name__________________________________Date__________________Class_____
Manufacturing Engineering
Programmable Logic Controllers
Troubleshooting Project Directions: Using the flowchart below identify up to 3 possible causes of the problems listed below. (Cont’d. next page) Copyright © Texas Education Agency, 2012. All rights reserved. 9 Components Pump ‐ Provides circulation of fluid through system (input) Flow meter ‐ indicates rate (quantity) of flow through system (output) Valves (input) Valve – A: Bypass to Reservoir (fluid storage) Valve – B: Provides fluid to Tank A Valve – C: Allows drainage of Tank A into Tank B Valve – D: Allows drainage of Tank B into distribution system Tank‐ provides fluid for facility operations or distribution to customer, etc. (output) Fluid Level Switch (output) F – 1: Tank B low level switch F – 2: Tank B high level switch F – 3: Tank A low level switch F – 4: Tank A high level switch F – 5: Reservoir (fluid storage) low level switch ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ Problem 1: Tank B will not shut down and continuously provides fluid to the distribution outlet. Problem 2: Fluid is continuously routed into reservoir and not into Tank A. Problem 3: Fluid will not circulate up to Tank A. Copyright © Texas Education Agency, 2012. All rights reserved. 10 Manufacturing Engineering
Programmable Logic Controllers
Troubleshooting Project Answer Key Problem 1: Tank B will not shut down and continuously provides fluid to the distribution outlet. Possible Cause: Defective Valve B or defective PLC Problem 2: Fluid is continuously routed into reservoir and not into tank A. Possible Cause: Defective Valve A or defective PLC Problem 3: Fluid will not circulate up to Tank A. Possible Cause: Defective pump, Valve B or defective PLC Copyright © Texas Education Agency, 2012. All rights reserved. 11 1
Notes:
Discuss the importance of automation in our society. Students should
understand that PLCs make these technology applications possible.
Stress the convenience and time saved by our automated processes.
Help students develop an appreciation of the value of PLC systems.
2
NOTES:
Definitions make a great warm up activity. Have
the class complete the Matching Definitions handout.
3
4
NOTES:
PLC devices were designed to replace the thousands of feet of industrial wiring
and thousands of electrical components required to operate an assembly line.
PLCs can control automated process for indefinite periods of time, as long as
all components are operating properly with a stable power supply.
PLCs are designed to be very durable and can with stand harsh operational
conditions involving extreme, temperature ranges, vibration, moisture, noise, etc.
5
NOTES:
Teachers: conduct research and identify additional PLC systems that you want
to discuss with your class.
6
Operation
This is an automated fluid distribution system that can be operated indefinitely.
Fluid is sent from Tank B for a variety of reasons (facility operations, distribution
to customer, etc.) PLCs control output of the entire operation base on inputs
from the fluid level switches in the system. PLCs operate the system by turning
the pump on or off and opening and closing the valves. Tank B provides fluid for
distribution, as the fluid level drops to a low point, F1 senses the condition and
the PLC opens Valve C to refill Tank B; when Tank B is full, F2 senses the
condition and the PLC closes Valve C. F3 senses the low condition of
Tank A and the PLC turns on the pump and opens Valve B. When Tank A is full,
F4 senses the condition and turns off the pump and closes Valve B. Any excess
fluid is routed through Valve A, back to the reservoir.
Components
Pump- Provides circulation of fluid through system (input)
Flow meter- indicates rate (quantity) of flow through system (output)
Valves (input)
Valve – A : Bypass to Reservoir (fluid storage)
Valve – B : Provides fluid to Tank A
Valve – C : Allows drainage of Tank A into Tank B
Valve – D : Allows drainage of Tank B into distribution system
7
Tank - provides fluid for facility operations or distribution to customer, etc.(output)
Fluid Level Switch (output)
F–1:Tank B low level switch; F–2:Tank B high level switch; F–3:Tank A low level
switch
F–4:Tank A high level switch; F–5:Reservoir (fluid storage) low level switch
7
Trouble shooting
The Troubleshooting process involves identifying the root cause of system malfunctions.
It is important to have a high level understanding of how the system operates to become
an effective troubleshooter.
Teachers: review the problems below, discuss the purpose of each component
in the system and discuss how the possible causes could cause the malfunctions.
Problem 1: System does not turn on.
Possible Causes:
- Malfunctioning electrical power source
- Main power switches or circuit breakers to PLC turned off
- Malfunctioning PLC unit
Problem 2: System is on, but no fluid is provided from Tank B.
Possible Causes:
- Malfunctioning valve C or D
- Malfunctioning F 1 or PLC not turning system on
- Malfunctioning pump
Problem 3: System is on, but no fluid is provided to Tank A.
Possible Causes:
8
- Malfunctioning valve B
- Malfunctioning F 3 or PLC not turning system on
- Malfunctioning pump
System Operation
This is an automated fluid distribution system that can be operated indefinitely.
Fluid is sent from Tank B for a variety of reasons (facility operations, distribution
to customer, etc.) PLCs control output the entire operation base on inputs from
the fluid level switches in the system. PLCs operate the system by turning the
pump on or off and opening and closing the valves. Tank B provides fluid for
distribution, as the fluid level drops to a low point, F1 senses the condition and
the PLC opens Valve C to refill Tank B; when tank B is full, F2 senses the condition
and the PLC closes valve C. F 3 senses the low condition of Tank A and the PLC
turns on the pump and opens Valve B. When Tank A is full, F4 senses the condition
and turns off the pump and closes Valve B. Any Excess fluid is routed through
Valve A, back to the reservoir.
Components
Pump- Provides circulation of fluid through system (input)
Flow meter- indicates rate (quantity) of flow through system (output)
Valves (input)
Valve – A : Bypass to reservoir (fluid storage),
Valve – B : Provides fluid to Tank A
Valve – C : Allows drainage of Tank A into Tank B
Valve – D : Allows drainage of Tank B
Tank - provides fluid for facility operations or distribution to customer, etc. (output)
Fluid Level Switch (output)
F–1:Tank B low level switch; F–2 :Tank B high level switch; F–3 :Tank A low level
switch;
F–4:Tank A high level switch; F–5: Reservoir (fluid storage) low level switch
8