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Programmable logic controllers (PLCs) have been an integral part of factory automation and industrial process control for decades. PLCs control a wide array of applications from simple lighting functions to environmental systems to chemical processing plants. These systems perform many functions, providing a variety of analog and digital input and output interfaces; signal processing; data conversion; and various communication protocols. All of the PLC's components and functions are centered around the controller, which is programmed for a specific task.

The basic PLC module must be sufficiently flexible and configurable to meet the diverse needs of different factories and applications. Input stimuli (either analog or digital) are received from machines, sensors, or process events in the form of voltage or current. The PLC must accurately interpret and convert the stimulus for the CPU which, in turn, defines a set of instructions to the output systems that control actuators on the factory floor or in another industrial environment

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  1. 1. Copyright © Appin Technology Lab
  2. 2. Copyright © Appin Technology Lab
  3. 3. 2Copyright © Appin Technology Lab • Introduction of PLC • Introduction of Scada • What is PLC • Importance of PLC • How PLC works • What is Scada • Importance of Scada • How Scada works • Components of SCADA • Scada Architectures • Why Plc-Scada • Benefits Of PLC-Scada • Scope of PLC-Scada TABLE OF CONTENT
  4. 4. 3Copyright © Appin Technology Lab INTRODUCTION OF PLC  Programmable logic controllers (PLCs) have been an integral part of factory automation and industrial process control for decades. PLCs control a wide array of applications from simple lighting functions to environmental systems to chemical processing plants. These systems perform many functions, providing a variety of analog and digital input and output interfaces; signal processing; data conversion; and various communication protocols. All of the PLC's components and functions are centered around the controller, which is programmed for a specific task.  The basic PLC module must be sufficiently flexible and configurable to meet the diverse needs of different factories and applications. Input stimuli (either analog or digital) are received from machines, sensors, or process events in the form of voltage or current. The PLC must accurately interpret and convert the stimulus for the CPU which, in turn, defines a set of instructions to the output systems that control actuators on the factory floor or in another industrial environment.
  5. 5. 4Copyright © Appin Technology Lab INTRODUCTION OF SCADA  SCADA (Supervisory Control and Data Acquisition) Now a days automation system contains PLCs and SCADA software. If you use PLC & SCADA combination the advantages you have is you have better monitoring and control of the plant and also you have access to the information the way you want. SCADA enables engineers, supervisors, managers and operators to view and interact with the workings of entire operations through graphical representation of their production process.  SCADA runs on a PC and is generally connected to various PLCs and other peripheral devices. It enables you to generate applications for the most demanding requirements of plant engineers, operators, supervisors and managers tailored precisely to the needs of each plant. SCADA constantly gathers data from the plant in real-time, stores and processes it in the database, evaluates and generates alarms, displays information to plant operators, supervisors and managers and can issue instructions to PLCs on the plant floor.
  6. 6. 5Copyright © Appin Technology Lab PLC: A PROGRAMMABLE LOGIC CONTROLLER  A Programmable Logic Controller, or PLC, is more or less a small computer with a built-in operating system (OS). This OS is highly specialized to handle incoming events in real time, or at the time of their occurrence.  The PLC has input lines where sensors are connected to notify upon events (e.g. temperature above/below a certain level, liquid level reached, etc.), and output lines to signal any reaction to the incoming events (e.g. start an engine, open/close a valve, etc.).  The system is user programmable. It uses a language called "Relay Ladder" or RLL (Relay Ladder Logic). The name of this language implies that the control logic of the earlier days, which was built from relays, is being simulated.
  7. 7. 6Copyright © Appin Technology Lab IMPORTANCE OF PLC  The PLC is primarily used to control machinery. A program is written for the PLC which turns on and off outputs based on input conditions and the internal program. In this aspect, a PLC is similar to a computer. However, a PLC is designed to be programmed once, and run repeatedly as needed. In fact, a crafty programmer could use a PLC to control not only simple devices such as a garage door opener, but their whole house, including switching lights on and off at certain times, monitoring a custom built security system, etc.  Most commonly, a PLC is found inside of a machine in an industrial environment. A PLC can run an automatic machine for years with little human intervention. They are designed to withstand most harsh environments.
  8. 8. 7Copyright © Appin Technology Lab HOW PLC LOOKS
  9. 9. 8Copyright © Appin Technology Lab HISTORY OF PLC  When the first electronic machine controls were designed, they used relays to control the machine logic (i.e. press "Start" to start the machine and press "Stop" to stop the machine). A basic machine might need a wall covered in relays to control all of its functions. There are a few limitations to this type of control.  Relays fail.  The delay when the relay turns on/off.  There is an entire wall of relays to design/wire/troubleshoot.  A PLC overcomes these limitations, it is a machine controlled operation.  Recent developments  PLCs are becoming more and more intelligent. In recent years PLCs have been integrated into electrical communications(Computer network)i.e., all the PLCs in an industrial environment have been plugged into a network which is usually hierarchically organized. The PLCs are then supervised by a control centre. There exist many proprietary types of networks. One type which is widely known is SCADA (Supervisory Control and Data Acquisition).
  10. 10. 9Copyright © Appin Technology Lab PLC: A PROGRAMMABLE LOGIC CONTROLLER
  11. 11. 10Copyright © Appin Technology Lab HOW PLC WORKS  How the PLC operates: The PLC is a purpose-built machine control computer designed to read digital and analog inputs from various sensors, execute a user defined logic program, and write the resulting digital and analog output values to various output elements like hydraulic and pneumatic actuators, indication lamps, solenoid coils, etc.  Scan cycle: Exact details vary between manufacturers, but most PLCs follow a 'scan-cycle‘s format.  Overhead includes testing I/O module integrity, verifying the user program logic hasn't changed, that the computer itself hasn't locked up (via a watchdog timer), and any necessary communications. Communications may include traffic over the PLC programmer port, remote I/O racks, and other external devices such as HMIs (Human Machine Interfaces).
  12. 12. 11Copyright © Appin Technology Lab  Input scan A 'snapshot' of the digital and analog values present at the input cards is saved to an input memory table. Logic execution The user program is scanned element by element, then rung by rung until the end of the program, and resulting values written to an output memory table .Output scan Values from the resulting output memory table are written to the output modules. Once the output scan is complete the process repeats itself until the PLC is powered down.  The time it takes to complete a scan cycle is, appropriately enough, the "scan cycle time", and ranges from hundreds of milliseconds (on older PLCs, and/or PLCs with very complex programs) to only a few milliseconds on newer PLCs, and/or PLCs executing short, simple code. HOW PLC WORKS
  13. 13. 12Copyright © Appin Technology Lab SCADA (SUPERVISORY CONTROL AND DATA ACQUISITION)  SCADA is a system operating with coded signals over communication channels so as to provide control of remote equipment (using typically one communication channel per remote station). The supervisory system may be combined with a data acquisition system by adding the use of coded signals over communication channels to acquire information about the status of the remote equipment for display or for recording functions. It is a type of industrial control system (ICS). Industrial control systems are computer-based systems that monitor and control industrial processes that exist in the physical world. SCADA systems historically distinguish themselves from other ICS systems by being large-scale processes that can include multiple sites, and large distances.
  14. 14. 13Copyright © Appin Technology Lab SCADA (SUPERVISORY CONTROL AND DATA ACQUISITION)
  15. 15. 14Copyright © Appin Technology Lab IMPORTANCE OF SCADA  Scada processes include industrial, infrastructure, and facility-based processes, as described below:  Industrial processes include those of manufacturing, production, power generation, fabrication, and refining, and may run in continuous, batch, repetitive, or discrete modes.  Infrastructure processes may be public or private, and include water treatment and distribution, wastewater collection and treatment, oil and gas pipelines, electrical power transmission and distribution, wind farms, civil defense siren systems, and large communication systems.  Facility processes occur both in public facilities and private ones, including buildings, airports, ships, and space stations. They monitor and control heating, ventilation, and air conditioning systems (HVAC), access, and energy consumption.
  16. 16. 15Copyright © Appin Technology Lab SCADA TOOL  SCADA can be a great tool while working in an environment where operational duties need to be monitored electronical communication instead of locally. For example, an operator can position a valve to open or closed as desired through SCADA without leaving the control station or the computer. The SCADA system also allows to switch a pump or motor on or off and has the capability of putting motors on a Hand operating status, off, or Automatic. Hand would be referring to operate the equipment locally, and automatic would be scaling the equipment to be operated according to set points the operator instructs on a computer that can communicate with the equipment through SCADA.
  17. 17. 16Copyright © Appin Technology Lab COMPONENTS OF SCADA  Remote terminal units (RTUs) connect to sensors in the process and convert sensor signals to digital data. They have telemetry hardware capable of sending digital data to the supervisory system, as well as receiving digital commands from the supervisory system. RTUs often have embedded control capabilities such as ladder logic in order to accomplish boolean logic operations.  Programmable logic controller (PLCs) connect to sensors in the process and converting sensor signals to digital data. PLCs have more sophisticated embedded control capabilities, typically one or more IEC 61131- 3 programming languages, than RTUs. PLCs do not have telemetry hardware, although this functionality is typically installed alongside them. PLCs are sometimes used in place of RTUs as field devices because they are more economical, versatile, flexible, and configurable.
  18. 18. 17Copyright © Appin Technology Lab  A telemetry system is typically used to connect PLCs and RTUs with control centers, data warehouses, and the enterprise. Examples of wired telemetry media used in SCADA systems include leased telephone lines and WAN circuits. Examples of wireless telemetry media used in SCADA systems include satellite (VSAT), licensed and unlicensed radio, cellular and microwave.  A data acquisition server is a software service which uses industrial protocols to connect software services, via telemetry, with field devices such as RTUs and PLCs. It allows clients to access data from these field devices using standard protocols.  A human–machine interface or HMI is the apparatus or device which presents processed data to a human operator, and through this, the human operator monitors and interacts with the process. The HMI is a client that requests data from a data acquisition server. COMPONENTS OF SCADA
  19. 19. 18Copyright © Appin Technology Lab  A Historian is a software service which accumulates time-stamped data, boolean events, and boolean alarms in a database which can be queried or used to populate graphic trends in the HMI. The historian is a client that requests data from a data acquisition server.  A supervisory (computer) system, gathering (acquiring) data on the process and sending commands (control) to the SCADA system.  Communication infrastructure connecting the supervisory system to the remote terminal units.  Various process and analytical instrumentation COMPONENTS OF SCADA
  20. 20. 19Copyright © Appin Technology Lab HOW SCADA WORKS  The term SCADA usually refers to centralized systems which monitor and control entire sites, or complexes of systems spread out over large areas (anything from an industrial plant to a nation). Most control actions are performed automatically by RTUs or by PLCs. Host control functions are usually restricted to basic overriding or supervisory level intervention. For example, a PLC may control the flow of cooling water through part of an industrial process, but the SCADA system may allow operators to change the set points for the flow, and enable alarm conditions, such as loss of flow and high temperature, to be displayed and recorded. The feedback control loop passes through the RTU or PLC, while the SCADA system monitors the overall performance of the loop.
  21. 21. 20Copyright © Appin Technology Lab  Data acquisition begins at the RTU or PLC level and includes meter readings and equipment status reports that are communicated to SCADA as required. Data is then compiled and formatted in such a way that a control room operator using the HMI can make supervisory decisions to adjust or override normal RTU (PLC) controls. Data may also be fed to a Historian, often built on a commodity Database Management System, to allow trending and other analytical auditing. HOW SCADA WORKS
  22. 22. 21Copyright © Appin Technology Lab  SCADA systems typically implement a distributed database, commonly referred to as a tag database, which contains data elements called tags or points. A point represents a single input or output value monitored or controlled by the system. Points can be either "hard" or "soft". A hard point represents an actual input or output within the system, while a soft point results from logic and math operations applied to other points. (Most implementations conceptually remove the distinction by making every property a "soft" point expression, which may, in the simplest case, equal a single hard point.)  SCADA systems are significantly important systems used in national infrastructures such as electric grids, water supplies and pipelines. However, SCADA systems may have security vulnerabilities, so the systems should be evaluated to identify risks and solutions implemented to mitigate those risks. HOW SCADA WORKS
  23. 23. 22Copyright © Appin Technology Lab SCADA ARCHITECTURE
  24. 24. 23Copyright © Appin Technology Lab  First generation: "Monolithic“  Early SCADA system computing was done by large minicomputers. Common network services did not exist at the time SCADA was developed. Thus SCADA systems were independent systems with no connectivity to other systems. The communication protocols used were strictly proprietary at that time. The first-generation SCADA system redundancy was achieved using a back-up mainframe system connected to all the Remote Terminal Unit sites and was used in the event of failure of the primary mainframe system. Some first generation SCADA systems were developed as "turn key" operations that ran on minicomputers such as the PDP-11 series made by the Digital Equipment Corporation SCADA ARCHITECTURE
  25. 25. 24Copyright © Appin Technology Lab  Second generation: "Distributed“  SCADA information and command processing was distributed across multiple stations which were connected through a LAN. Information was shared in near real time. Each station was responsible for a particular task thus making the size and cost of each station less than the one used in First Generation. The network protocols used were still not standardized. Since the protocols were proprietary, very few people beyond the developers knew enough to determine how secure a SCADA installation was. Security of the SCADA installation was usually overlooked. SCADA ARCHITECTURE
  26. 26. 25Copyright © Appin Technology Lab  Third generation: "Networked“  Similar to a distributed architecture, any complex SCADA can be reduced to simplest components and connected through communication protocols. In the case of a networked design, the system may be spread across more than one LAN network and separated geographically. Several distributed architecture SCADAs running in parallel, with a single supervisor and historian, could be considered a network architecture. This allows for a more cost effective solution in very large scale systems. SCADA ARCHITECTURE
  27. 27. 26Copyright © Appin Technology Lab  Fourth generation: "Internet of Things“  With the commercial availability of cloud computing, SCADA systems have increasingly adopted Internet of Things technology to significantly reduce infrastructure costs and increase ease of maintenance and integration. As a result SCADA systems can now report state in near real-time and use the horizontal scale available in cloud environments to implement more complex control algorithms than are practically feasible to implement on traditional programmable logic controllers. Further, the use of open network protocols such as TLS inherent in Internet of Things technology provides a more readily comprehendable and manageable security boundary than the heterogeneous mix of proprietary network protocols typical of many decentralized SCADA implementations. SCADA ARCHITECTURE
  28. 28. 27Copyright © Appin Technology Lab
  29. 29. 28Copyright © Appin Technology Lab WHY PLC-SCADA  In recent times, all most every industry use automation or control systems for working. Every industry needs more engineers to grow their production rate. Foreign countries have also understood the importance of automation. It is a type of control system which involves information technology and reduces the human manually works in production. For automation industry PLC and SCADA are the most important tools, without these tools automation is not possible. It plays a vital role in the world economy as it replaces all manual systems power.  If you want to get a best job in automation industry, you must have an idea about industry’s requirement. Almost every industry needs professionally trained students who have some experience and detailed knowledge about PLC-Scada technology. Candidate needs to get trained in the same, because Training helps them to get practical knowledge and skills that required to get placed in a famous industry. By getting trained with the professionals who have industry experience, you will get the industry exposure with the industrial training project as well.
  30. 30. 29Copyright © Appin Technology Lab WHY APPIN  If you are looking for a better career in an automation industry after completing your degree, You should get trained from the company who has expertise in the same. Appin is a well-known company in the field of Information Technology which provides industrial training for all courses related to IT, electronics and telecom field. We also provides the Job Oriented Training programs in Information Security/IRM/Secured Application programming/ Secured Mobile Application Development programming in Android, BlackBerry, iOS. Our placement record is better than other players in the market.  Our training programs are on the latest technologies with the updated versions & advanced concepts. Like cloud computing PLC-Scada.
  31. 31. 30Copyright © Appin Technology Lab HOW SCADA LOOKS
  32. 32. 31Copyright © Appin Technology Lab MANUFACTURING INDUSTRIES
  33. 33. 32Copyright © Appin Technology Lab BENEFITS OF PLC-SCADA  PLC and SCADA are the success behind the automation industry. PLC is designed in such a way that it can be used to control multiple inputs and outputs and it can be handled in extreme temperature changes. Without these two automation concepts the automation industry fails. So there is a huge demand for skilled manpower in PLC and SCADA in automation industry. We cannot even think of surviving without this technology even for a day. If the system fails then there would be losses of cores of rupees. After the application of PLC and SCADA technology in Industrial automation process.  It is creating a lot of employment opportunities  There is a huge demand for skilled manpower in this sector  Reduces time  Reduces Cost  Profit maximization  Economies of scale  Improved Productivity  Quality output  Increased Accuracy and speed
  34. 34. 33Copyright © Appin Technology Lab SCOPE OF PLC SCADA  If you have PLC-Scada training certificate , you will get a chance in different companies on different profiles specially in the manufacturing industry. Some of the profiles are mentioned below:- 1. PLC-SCADA Trainee 2. PLC-SCADA Software Engineer 3. Automation and Drives manufacturer at global firms 4. PLC SCADA HMI AC DC 5. Application Engineer – PLC-Scada 6. Electrical Maintenance automation Manager maintenance Manager PLC SCADA 7. Automation Engineer. 8. Instrumentation Engineer.
  35. 35. 34Copyright © Appin Technology Lab COMPANIES HIRING FOR PLC SCADA and many more….
  36. 36. 35Copyright © Appin Technology Lab For more details please visit:  
  37. 37. 36Copyright © Appin Technology Lab