PLC and Industrial Automation - Technology OverviewNereus Fernandes
Basic Theory, PLC Types
SCADA-HMI
Drive Control using PLC
Protocols-Modbus, OPC UA
PLC Selection, Programming Guidelines
Industrial Automation Hierarchy
Other Closely Related Controllers and Networks
Safety Instrumented Systems
Building Automation Systems
Substation Automation Systems & Electrical SCADA
DCS (Distributed Control System)
RTU (Remote Terminal Unit)
Machine Vision
Position & Motion Systems
Robotics
CNC Machines
PAC (Programmable Automation Controller)
Emerging Technologies
MQTT Protocol & PLC intergation with (Industrial) IIoT and the Cloud
Assisted / Augmented Reality
Simulation & Virtual Reality
SCADA – support for Pharma Regulations, GeoSCADA
H/w & S/w to build a PLC, HMI and SCADA System
Industrial Cyber Security
Dual Use Technology
OPC UA mit der SIMATIC S7-1200/1500 und PythonJohannes Kinzig
In diesem Read-Deck werden wir auf einer SIMATIC S7-1200 bzw. S7-1500 den OPC UA Server aktivieren, konfigurieren und mit einem Python Skript auf den freigegebenen Speicherbereich zugreifen.
PLC and Industrial Automation - Technology OverviewNereus Fernandes
Basic Theory, PLC Types
SCADA-HMI
Drive Control using PLC
Protocols-Modbus, OPC UA
PLC Selection, Programming Guidelines
Industrial Automation Hierarchy
Other Closely Related Controllers and Networks
Safety Instrumented Systems
Building Automation Systems
Substation Automation Systems & Electrical SCADA
DCS (Distributed Control System)
RTU (Remote Terminal Unit)
Machine Vision
Position & Motion Systems
Robotics
CNC Machines
PAC (Programmable Automation Controller)
Emerging Technologies
MQTT Protocol & PLC intergation with (Industrial) IIoT and the Cloud
Assisted / Augmented Reality
Simulation & Virtual Reality
SCADA – support for Pharma Regulations, GeoSCADA
H/w & S/w to build a PLC, HMI and SCADA System
Industrial Cyber Security
Dual Use Technology
OPC UA mit der SIMATIC S7-1200/1500 und PythonJohannes Kinzig
In diesem Read-Deck werden wir auf einer SIMATIC S7-1200 bzw. S7-1500 den OPC UA Server aktivieren, konfigurieren und mit einem Python Skript auf den freigegebenen Speicherbereich zugreifen.
Implementation of T-Junction Traffic Light Control System Using Simatic S7-20...IJERA Editor
A conventional traffic light control system is designed by using devices such as timers, relays and
contactors etc. The critical timing operation is required to be carried out under the existence of heavy
traffic situations. This conventional practice leads to many problems that need additional maintenance
cost and subsequent delay for a long time. With the help of a PLC, the requirement of fast automation
and effective optimization of traffic light control system can be achieved. Use of PLC helps us to
develop this process not only for traffic signal on the roads, but also on the movement of trains and
the transfer of containers in ports in maritime works. In order to provide a solution to the above
problem, this paper introduces an execution and implementation of T-junction traffic control system
using SEIMENS S7-200 PLC. Programming in PLC is written in ladder logic with the help of STEP7
MICROWIN software
A programmable logic controller (PLC) is a specialized used to control machines and process. It uses a programmable memory to store instructions and specific functions that include On/Off control, timing, counting, seque-
-ncing, arithmetic and data handling systems.
Programmable Logic Controller (PLC Part 3)Priyanshu
Hello Everyone!
This is the best ppt series on 'Programmable Logic Controller' that you can ever find. I have covered all the topics from basics to advanced that can be learned easily. These notes are also helpful for students for preparing any competitive exam and also for university exams.
Learn and Enjoy!
Thank You!
Implementation of T-Junction Traffic Light Control System Using Simatic S7-20...IJERA Editor
A conventional traffic light control system is designed by using devices such as timers, relays and
contactors etc. The critical timing operation is required to be carried out under the existence of heavy
traffic situations. This conventional practice leads to many problems that need additional maintenance
cost and subsequent delay for a long time. With the help of a PLC, the requirement of fast automation
and effective optimization of traffic light control system can be achieved. Use of PLC helps us to
develop this process not only for traffic signal on the roads, but also on the movement of trains and
the transfer of containers in ports in maritime works. In order to provide a solution to the above
problem, this paper introduces an execution and implementation of T-junction traffic control system
using SEIMENS S7-200 PLC. Programming in PLC is written in ladder logic with the help of STEP7
MICROWIN software
A programmable logic controller (PLC) is a specialized used to control machines and process. It uses a programmable memory to store instructions and specific functions that include On/Off control, timing, counting, seque-
-ncing, arithmetic and data handling systems.
Programmable Logic Controller (PLC Part 3)Priyanshu
Hello Everyone!
This is the best ppt series on 'Programmable Logic Controller' that you can ever find. I have covered all the topics from basics to advanced that can be learned easily. These notes are also helpful for students for preparing any competitive exam and also for university exams.
Learn and Enjoy!
Thank You!
Mechatronics is a multidisciplinary field that refers to the skill sets needed in the contemporary, advanced automated manufacturing industry. At the intersection of mechanics, electronics, and computing, mechatronics specialists create simpler, smarter systems.
This is a small project on Siemens PLC Step 7 models. The project required lot of lateral thinking and logical decision making in order to develop programs for the traffic light management for the entire chandigarh city. The project is known as Total Traffic Security & Management (TTSM)
Basics and applications of programmable logic controller (plc)Ali Altahir
PLC is a multipurpose clock-driven memory-based electronic device which is also known as a specialized industrial computer which deals with different level of complexity and control system.
Best core Industrial Training in Delhi/NCRBharti Singh
SR Thermonix Technologies is a leading company of SR Turbo Energy Pvt. Ltd. based Delhi/NCR. SR Thermonix Technologies is a best Automation training company who provides Industrial Training, Core Industrial training, PLC SCADA training, Power Plant training, Job Guaranteed PLC SCADA training, Placement assistance PLC SCADA training, Automation PLC SCADA training for Electrical engineer, Electronic engineer, Instrumentation engineer,Mechanical engineer.We provide Best core Industrial training. This training is Job Oriented training. We are looking EE/EEE/ECE/EIE/ICE/ME in B.Tech/Diploma for Core Industrial PLC SCADA training.
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Summer Internship Report For PLC Programming of Traffic light through Ladder ...Aman Gupta
For free download Subscribe to https://www.youtube.com/channel/UCTfiZ8qwZ_8_vTjxeCB037w and Follow https://www.instagram.com/fitrit_2405/ then please contact +91-9045839849 over WhatsApp.
An industrial PLCs system is used for the development of the controls of machinery. This paper describes the PLCs systems in terms of their architecture, their interface to the process hardware, the functionality and the application development facilities they provide. Some attention is also paid to the industrial standards to which they abide their planned evolution as well as the potential benefits of their use. Ladder Logic is a graphical programming language, initially programmed with simple contacts that simulates the opening and closing of relays. Ladder Logic programming has been expanded to include functions such as Counters, Timers, shift Registers and math operations. Ladder logic is a method of drawing electrical logic schematics. It is now a graphical language very popular for programming Programmable Logic Controllers (PLCs). It was originally invented to describe logic made from relays. The name is based on the observation that programs in this language resemble ladders, with two vertical "rails" and a series of horizontal "rungs" between them.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
Online aptitude test management system project report.pdfKamal Acharya
The purpose of on-line aptitude test system is to take online test in an efficient manner and no time wasting for checking the paper. The main objective of on-line aptitude test system is to efficiently evaluate the candidate thoroughly through a fully automated system that not only saves lot of time but also gives fast results. For students they give papers according to their convenience and time and there is no need of using extra thing like paper, pen etc. This can be used in educational institutions as well as in corporate world. Can be used anywhere any time as it is a web based application (user Location doesn’t matter). No restriction that examiner has to be present when the candidate takes the test.
Every time when lecturers/professors need to conduct examinations they have to sit down think about the questions and then create a whole new set of questions for each and every exam. In some cases the professor may want to give an open book online exam that is the student can take the exam any time anywhere, but the student might have to answer the questions in a limited time period. The professor may want to change the sequence of questions for every student. The problem that a student has is whenever a date for the exam is declared the student has to take it and there is no way he can take it at some other time. This project will create an interface for the examiner to create and store questions in a repository. It will also create an interface for the student to take examinations at his convenience and the questions and/or exams may be timed. Thereby creating an application which can be used by examiners and examinee’s simultaneously.
Examination System is very useful for Teachers/Professors. As in the teaching profession, you are responsible for writing question papers. In the conventional method, you write the question paper on paper, keep question papers separate from answers and all this information you have to keep in a locker to avoid unauthorized access. Using the Examination System you can create a question paper and everything will be written to a single exam file in encrypted format. You can set the General and Administrator password to avoid unauthorized access to your question paper. Every time you start the examination, the program shuffles all the questions and selects them randomly from the database, which reduces the chances of memorizing the questions.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Water billing management system project report.pdfKamal Acharya
Our project entitled “Water Billing Management System” aims is to generate Water bill with all the charges and penalty. Manual system that is employed is extremely laborious and quite inadequate. It only makes the process more difficult and hard.
The aim of our project is to develop a system that is meant to partially computerize the work performed in the Water Board like generating monthly Water bill, record of consuming unit of water, store record of the customer and previous unpaid record.
We used HTML/PHP as front end and MYSQL as back end for developing our project. HTML is primarily a visual design environment. We can create a android application by designing the form and that make up the user interface. Adding android application code to the form and the objects such as buttons and text boxes on them and adding any required support code in additional modular.
MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software. It is a stable ,reliable and the powerful solution with the advanced features and advantages which are as follows: Data Security.MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
6th International Conference on Machine Learning & Applications (CMLA 2024) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Applications.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
1. Lecture – Introduction to PLC's MME 486 – Fall 2006 1 of 47
Introduction to
Programmable Logic Controllers
(PLC's)
Industrial Control Systems
Fall 2006
2. Lecture – Introduction to PLC's MME 486 – Fall 2006 2 of 47
The Need for PLCs
• Hardwired panels were very time consuming
to wire, debug and change.
• GM identified the following requirements for
computer controllers to replace hardwired
panels.
– Solid-state not mechanical
– Easy to modify input and output devices
– Easily programmed and maintained by plant
electricians
– Be able to function in an industrial environment
3. Lecture – Introduction to PLC's MME 486 – Fall 2006 3 of 47
The First Programmable Logic
Controllers (PLCs)
• Introduced in the late 1960’s
• Developed to offer the same functionality as
the existing relay logic systems
• Programmable, reusable and reliable
– Could withstand a harsh industrial environment
– They had no hard drive, they had battery backup
– Could start in seconds
– Used Ladder Logic for programming
4. Lecture – Introduction to PLC's MME 486 – Fall 2006 4 of 47
Programmable Logic Controller
• A programmable logic controller (PLC)
is a specialized computer used to
control machines and process.
• It uses a programmable memory to
store instructions and specific functions
that include On/Off control, timing,
counting, sequencing, arithmetic, and
data handling
5. Lecture – Introduction to PLC's MME 486 – Fall 2006 5 of 47
Advantages of PLC Control
Systems
• Flexible
• Faster response time
• Less and simpler wiring
• Solid-state - no moving parts
• Modular design - easy to repair and expand
• Handles much more complicated systems
• Sophisticated instruction sets available
• Allows for diagnostics “easy to troubleshoot”
• Less expensive
6. Lecture – Introduction to PLC's MME 486 – Fall 2006 6 of 47
Advantages of a PLC Control System
Eliminates much of the hard wiring that was associated
with conventional relay control circuits.
The program takes
the place of much of
the external wiring
that would be required
for control of a process.
7. Lecture – Introduction to PLC's MME 486 – Fall 2006 7 of 47
Advantages of a PLC Control System
Increased Reliability:
Once a program has been written and tested it can be downloaded to
other PLCs.
Since all the logic is
contained in the PLC’s
memory, there is no
chance of making a
logic wiring error.
Conversely ......
8. Lecture – Introduction to PLC's MME 486 – Fall 2006 8 of 47
Advantages of a PLC Control System
More Flexibility:
Original equipment manufacturers (OEMs) can provide system updates
for a process by simply sending out a new program.
It is easier to create
and change a program
in a PLC than to wire
and rewire a circuit.
End-users can modify
the program in the
field.
9. Lecture – Introduction to PLC's MME 486 – Fall 2006 9 of 47
Advantages of a PLC Control System
Lower Costs:
Originally PLCs were designed to replace relay control logic. The cost
savings using PLCs have been so significant that relay control is
becoming obsolete, except for power applications.
Generally, if an application
requires more than about
6 control relays, it will
usually be less expensive
to install a PLC.
10. Lecture – Introduction to PLC's MME 486 – Fall 2006 10 of 47
Advantages of a PLC Control System
Communications Capability:
A PLC can communicate with other controllers or computer equipment.
They can be networked to
perform such functions as:
supervisory control, data
gathering, monitoring
devices and process
parameters, and downloading
and uploading of programs.
11. Lecture – Introduction to PLC's MME 486 – Fall 2006 11 of 47
Advantages of a PLC Control System
Faster Response Time:
PLCs operate in real-time which means that an event taking place in the
field will result in an operation or output taking place.
Machines that process
thousands of items per
second and objects that
spend only a fraction of
a second in front of a
sensor require the PLC’s
quick response capability.
12. Lecture – Introduction to PLC's MME 486 – Fall 2006 12 of 47
Advantages of a PLC Control System
Easier To Troubleshoot:
PLCs have resident diagnostic and override functions allowing users to
easily trace and correct software and hardware problems.
The control program
can be watched in
real-time as it
executes to find
and fix problems
15. Lecture – Introduction to PLC's MME 486 – Fall 2006 15 of 47
PLC Architecture
• An open architecture design allows the system to be
connected easily to devices and programs made by
other manufacturers.
• A closed architecture or proprietary system, is one
whose design makes it more difficult to connect devices
and programs made by other manufacturers.
NOTE: When working with PLC systems that are
proprietary in nature you must be sure that any generic
hardware or software you use is compatible with your
particular PLC.
16. Lecture – Introduction to PLC's MME 486 – Fall 2006 16 of 47
I/O Configurations
Fixed I/O
• Is typical of small PLCs
• Comes in one package, with
no separate removable units.
• The processor and I/O are
packaged together.
• Lower in cost – but
lacks flexibility.
17. Lecture – Introduction to PLC's MME 486 – Fall 2006 17 of 47
I/O Configurations
Modular I/O
Is divided by compartments
into which separate modules
can be plugged.
This feature greatly increases
your options and the unit’s
flexibility. You can choose
from all the modules available
and mix them in any way you
desire.
18. Lecture – Introduction to PLC's MME 486 – Fall 2006 18 of 47
I/O Configurations
Modular I/O
When a module slides into the rack,
it makes an electrical connection with a series of
contacts - called the backplane. The backplane
is located at the rear of the rack.
19. Lecture – Introduction to PLC's MME 486 – Fall 2006 19 of 47
Power Supply
• Supplies DC power to other
modules that plug into the rack.
• In large PLC systems, this
power supply does not
normally supply power to the
field devices.
• In small and micro PLC systems, the power supply
is also used to power field devices.
20. Lecture – Introduction to PLC's MME 486 – Fall 2006 20 of 47
Processor (CPU)
Processor
Module
• Is the “brain” of the PLC.
• Consists of a microprocessor
for implementing the logic, and
controlling the communications
among the modules.
• Designed so the desired circuit can be
entered in relay ladder logic form.
• The processor accepts input data from
various sensing devices, executes the
stored user program, and sends
appropriate output commands to
control devices.
21. Lecture – Introduction to PLC's MME 486 – Fall 2006 21 of 47
I/O Section
Consists of:
• Input modules
• Output modules.
22. Lecture – Introduction to PLC's MME 486 – Fall 2006 22 of 47
I/O Section
Input Module
• Forms the interface
by which input field
devices are connected
to the controller.
• The terms “field” and
“real world”are used to
distinguish actual external
devices that exist and must
be physically wired into the system.
23. Lecture – Introduction to PLC's MME 486 – Fall 2006 23 of 47
I/O Section
Output Module
• Forms the interface
by which output field
devices are connected
to the controller.
• PLCs employ an
optical isolator which
uses light to electrical-
ly isolate the internal
components from the
input and output
terminals.
24. Lecture – Introduction to PLC's MME 486 – Fall 2006 24 of 47
Programming Device
PC with appropriate
software
• A personal computer (PC) is the most commonly used
programming device
• The software allows users to create, edit, document,
store and troubleshoot programs
• The personal computer communicates with the PLC
processor via a serial or parallel data communications link
25. Lecture – Introduction to PLC's MME 486 – Fall 2006 25 of 47
Programming Device
Hand-held unit
with display
• Hand-held programming devices are sometimes used to
program small PLCs
• They are compact, inexpensive, and easy to use, but
are not able to display as much logic on screen as a
computer monitor
26. Lecture – Introduction to PLC's MME 486 – Fall 2006 26 of 47
Programming Device
• Hand-held units are often used on the factory floor
for troubleshooting, modifying programs, and
transferring programs to multiple machines.
Hand-held unit
with display
27. Lecture – Introduction to PLC's MME 486 – Fall 2006 27 of 47
PLC Mixer Process Control Problem
Mixer motor to automatically
stir the liquid in the vat
when the temperature and
pressure reach preset values
Alternate manual
pushbutton control
of the motor to be
provided
The temperature and
pressure sensor switches
close their respective contacts when conditions reach
their preset values
28. Lecture – Introduction to PLC's MME 486 – Fall 2006 28 of 47
Process Control Relay Ladder Diagram
Motor starter coil is energized when both the pressure
and temperature switches are closed or when the manual
pushbutton is pressed
29. Lecture – Introduction to PLC's MME 486 – Fall 2006 29 of 47
PLC Input Module Connections
• The same input field
devices are used
• These devices are
wired to the input
module according to
the manufacturer’s
labeling scheme
30. Lecture – Introduction to PLC's MME 486 – Fall 2006 30 of 47
PLC Output Module Connections
Same output field
device is used and
wired to the output
module
Triac switches motor
ON and OFF in accordance
with the control signal from
the processor
Triac
31. Lecture – Introduction to PLC's MME 486 – Fall 2006 31 of 47
PLC Ladder Logic Program
• The format used is similar to that of the hard-wired
relay circuit
32. Lecture – Introduction to PLC's MME 486 – Fall 2006 32 of 47
PLC Ladder Logic Program
The symbols represent instructions
33. Lecture – Introduction to PLC's MME 486 – Fall 2006 33 of 47
PLC Ladder Logic Program
The numbers represent addresses
34. Lecture – Introduction to PLC's MME 486 – Fall 2006 34 of 47
PLC Ladder Logic Program
• I/O address format will differ, depending on the PLC
manufacturer. You give each input and output device
an address. This lets the PLC know where they are
physically connected
35. Lecture – Introduction to PLC's MME 486 – Fall 2006 35 of 47
Entering And Running The PLC Program
To enter the program into the PLC, place
the processor in the PROGRAM mode and
enter the instructions one-by-one using
the programming device
To operate the program, the controller
is placed in the RUN mode, or operating
cycle
36. Lecture – Introduction to PLC's MME 486 – Fall 2006 36 of 47
PLC Operating Cycle
During each operating cycle, the controller examines the
status of input devices, executes the user program, and
changes outputs accordingly
The completion of one cycle
of this sequence is called
a scan. The scan time, the
time required for one full
cycle, provides a measure
of the speed of response
of the PLC
37. Lecture – Introduction to PLC's MME 486 – Fall 2006 37 of 47
PLC Operating Cycle
The can be considered to represent a coil that,
when energized, will close a set of contacts.
Each can be though of as a set of normally
open contacts
38. Lecture – Introduction to PLC's MME 486 – Fall 2006 38 of 47
PLC Operating Cycle
Coil O/1 is energized when contacts I/1 and I/2 are closed
or when contact I/3 is closed. Either of these conditions
provides a continuous path from left to right across the
rung that includes the coil.
39. Lecture – Introduction to PLC's MME 486 – Fall 2006 39 of 47
Modifying A PLC Program
Relay ladder diagram for
modified process.
The change requires that the manual pushbutton
control should be permitted to operate at any pressure but
not unless the specified temperature setting has been
reached.
40. Lecture – Introduction to PLC's MME 486 – Fall 2006 40 of 47
Modifying A PLC Program
Relay ladder diagram for
modified process.
If a relay system were used, it would require some
rewiring of the system, as shown, to achieve the
desired change.
41. Lecture – Introduction to PLC's MME 486 – Fall 2006 41 of 47
Modifying A PLC Program
PLC ladder logic diagram for
modified process.
If a PLC is used, no rewiring is necessary!
The inputs and outputs are still the same.
All that is required is to change the PLC program
42. Lecture – Introduction to PLC's MME 486 – Fall 2006 42 of 47
PLC
- Operates in the industrial
environment
- Is programmed in relay
ladder logic
- Has no keyboard, CD drive,
monitor, or disk drive
- Has communications ports,
and terminals for input and
output devices
PLCs Versus Personal Computers
Same basic
architecture
PC
- Capable of executing several
programs simultaneously, in
any order
- Some manufacturers have
software and interface cards
available so that a PC can do
the work of a PLC
43. Lecture – Introduction to PLC's MME 486 – Fall 2006 43 of 47
PC Based Control Systems
Advantages
- Lower initial cost
- Less proprietary hardware
and software required
- Straightforward data exchange
with other systems
- Speedy information processing
- Easy customization
44. Lecture – Introduction to PLC's MME 486 – Fall 2006 44 of 47
PLC Size Classification
Criteria
- Number of inputs and outputs (I/O count)
- Cost
- Physical size
Nano PLC
- Smallest sized PLC
- Handles up to 16 I/O points
Micro PLC
- Handles up to 32 I/O points
45. Lecture – Introduction to PLC's MME 486 – Fall 2006 45 of 47
Allen-Bradley PLC-5 Family
- Handles several thousand I/O
points
Allen-Bradley SLC-500 Family
- Handles up to 960 I/O points
PLC Size Classification
46. Lecture – Introduction to PLC's MME 486 – Fall 2006 46 of 47
PLC Instruction Set
The instruction set for a particular PLC type lists the
different types of instructions supported.
An instruction is a command that will cause a PLC
to perform a certain predetermined operation.
47. Lecture – Introduction to PLC's MME 486 – Fall 2006 47 of 47
Typical PLC Instructions
XIC (Examine ON) . . . . . . . Examine a bit for an ON condition
XIO (Examine OFF) . . . . . . Examine a bit for an OFF condition
OTE (Output Energize) . . . . Turn ON a bit (non retentive)
OTL (Output Latch) . . . . . . Latch a bit (retentive)
OTU (Output Unlatch) . . . . Unlatch a bit (retentive)
TOF (Timer Off-Delay) . . . . . Turn an output ON or OFF after its
rung has been OFF a preset time
interval
TON (Timer On-Delay) . . . . Turn an output ON or OFF after its
rung has been ON for a preset time
interval
CTD (Count Down) . . . . . . . Use a software counter to count down
from a specified value
CTU (Count Up) . . . . . . . . . Use a software counter to count up
to a specified value