PLC, by Mohamed Al-Emam, Session 1


Published on

One of my past projects to share knowledge in CSED foundation in CAT. presented in the Mansoura Faculty of Engineering. 02-02-2009

Published in: Technology, Business
No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • control systems may classify to open or closed loop, analog or digital. Yet we can classify control systems in other ways, which have to do with applications to. Process control Sequential control Motion control
  • FPGA==can prog by VHDL or VerilogClosed sys contain sensorz
  • PAC ==describes this new generation of industrial controllers that combines the functionality of a PLC and a PC.As the technological differences between PC and PLC wane, a new class of controllers is emerging for engineers who require higher loop rates, advanced control algorithms, more analog capabilities, and better integration with the enterprise network. The Programmable Automation Controller (PAC) describes this new generation of industrial controllers that combines the functionality of a PLC and a PC.
  • Open Frame PLC(Triangle Research Inc., Pte. Ltd.)single printed circuit board as shown in Figure 2-1.They are sometimes called single board PLCs or open frame PLCs. These are totallyself contained (with the exception of a power supply) and, when installed in a system, theyare simply mounted inside a controls cabinet on threaded standoffs. Screw terminals onthe printed circuit board allow for the connection of the input, output, and power supplywires. These units are generally not expandable, meaning that extra inputs, outputs, andmemory cannot be added to the basic unit. However, some of the more sophisticatedmodels can be linked by cable to expansion boards that can provide extra I/O. Therefore,with few exceptions, when using this type of PLC, the system designer must take care tospecify a unit that has enough inputs, outputs, and programming capability to handle boththe present need of the system and any future modifications that may be required. Singleboard PLCs are very inexpensive (some less than $100), easy to program, small, andconsume little power, but, generally speaking, they do not have a large number of inputsand outputs, and have a somewhat limited instruction set. They are best suited to small,relatively simple control applications.
  • (Omron Electronics) Modularized PLC
  • usually based upon the required inputs, outputs and functions of the controller. The first decision is the type of controller; rack, mini, micro, or software based. This decision will depend on After the planning phase of the design, the equipment can be ordered. This deci-sion is usually based upon the required inputs, outputs and functions of the controller. The first decision is the type of controller; rack, mini, micro, or software based. This decision will depend upon the basic criteria listed below.• Number of logical inputs and outputs.• Memory - Often 1K and up. Need is dictated by size of ladder logic program. A ladder element will take only a few bytes, and will be specified in manufactur-ers documentation.• Number of special I/O modules - When doing some exotic applications, a large number of special add-on cards may be required.• Scan Time - Big programs or faster processes will require shorter scan times. And, the shorter the scan time, the higher the cost. Typical values for this are 1 microsecond per simple ladder instruction• Communications - Serial and networked connections allow the PLC to be pro-grammed and talk to other PLCs. The needs are determined by the application.• Software - Availability of programming software and other tools determines the programming and debugging ease.The process of selecting a PLC can be broken into the steps listed below.1. Understand the process to be controlled (Note: This is done using the design sheets in the previous chapter).• List the number and types of inputs and outputs.• Determine how the process is to be controlled.
  • Tissue Packing Machine
  • ammonia and ethylene processing
  • سابك السعودية
  • This is an intro to a point in next session Errors fatal or non
  • Von Neumann architecture memory “memory-mapped I/O “accesses hardware by reading and writing to specific memory locations, using the same assembler language instructions that computer would normally use to access memory. 
  • Omron E2K-X4ME2 Proximity Switch Capacitive 10 TO 30 Vdc Detecting Distance 4MM OMRON Inductive Proximity Switches
  • Is a device used to detect the presence of an object by using a light transmitter, often infrared, and a photoelectric receiver. They are used extensively in industrial manufacturing. There are three different functional types, opposed, retro reflective, and proximity-sensing.
  • PLC, by Mohamed Al-Emam, Session 1

    1. 1. Session 01By Emamof Presented in 02-02-2009
    2. 2. TARGET TO  CONTROL SYS. Automatic Controller WHAT Origin of PLC History Sizes of PLC’s Cycle of Operation Which APPLICATIONS N REAL PLC H.W Components: INPUT TO PLC ,SENSING CONCEPTS
    3. 3. Open loopClosed loop Control System
    4. 4. AnalogDigital Control System
    5. 5. Control systemMotion Sequential
    6. 6. Batch Processhas a beginning and an end “complete product control process” , Some applications require that specific quantities of raw materials be combined in specific ways for particular durations to produce an intermediate or end result.Example:production of food and medicine.
    7. 7. Continuous ProcessOften, a physical system is represented though variables that are smooth and uninterrupted in time.Example :control of the water temperature in a heating jacket,
    8. 8. DiscreteIt is Not independent, Most discrete manufacturing involves the production of discrete pieces of productExamples : metal stamping. automotive production.
    9. 9. Hybrid Applications having elements of discrete, batch and continuous process control are often called hybrid applications.
    10. 10. Sequential ControlControl a process that is a series of tasks to be performed (sequence of operation ),each task is performed under :- Time driven . Common in open loop sys Event driven . Common in closed loop sysExample washing machineIn PLC the SFC is powerful Lang for it .
    11. 11. Motion ControlControlling motion in electromechanical sys Rotational or Linear by Servomotor. Digital by NC (Numerical Control). 3 dimension by Robotic.
    13. 13. Automatic controllers  µC==Microcontroller.  FPGA not FBGA.  PC  Mr. PLC  DCS== Distributed Control System  SCADA == Supervisory Control And Data Acquisition  CNC == Computer Numerical Control  PAC ==Programmable Automation Controller
    14. 14. SCADA
    15. 15. WHAT Programmable logic controllers, also called programmable controllers or PLCs, are solid-state members of the computer family, using integrated circuits instead of electromechanical devices to implement control functions. They are capable of storing instructions, such as sequencing, timing, counting, arithmetic, dat a manipulation, and communication, to control industrial machines and processes
    16. 16. Intro 2 Microprocessor andMicrocontroller world.
    17. 17. Microprocessor The block that will have a built in capability to Add “multiply, divide, subtract”, and move its contents from one memory location onto another is called "central processing unit" (CPU).
    18. 18. Characteristics differentiatemicroprocessors Instruction set The set of instructions that the microprocessor can execute bandwidth The number of bits processed in a single instruction clock speed Given in megahertz MHz the clock speed determines how many instructions per second the processor can execute
    19. 19. MicrocontrollerA microcontroller (also MCU or µC) is a functional computer system-on-a-chip.It contains a processor core, memory, and programmable input/output peripherals.
    20. 20. Microcontroller Architecture
    21. 21. Why Coz we can say Microcontroller= Microprocessor +Memory +i/o Peripherals. PLC’s=Microcontroller +I/O Interfaces.
    22. 22. Dick Morley==Richard E. MorleyFounder of Modicon (now Schneider Automation, Inc)
    23. 23. History of PLCs The first Programmable Logic Controllers were designed and developed by Modicon as a relay replacer for GM and Landis The first PLC, model 084, was invented by Dick Morley in 1969 The first commercial successful PLC, the 184, was designed by Michael Greenberg in 1973
    24. 24. Sizes of PLC’s
    25. 25. Single Board PLCs “ Open FramePLCs”.
    26. 26. PLC System With High-DensityI/O (64-point modules).
    27. 27. PLC market canbe segmentedinto five groups:1. micro2. small3. medium4. large5. very large
    28. 28. Cycle of operate PLC’s input  scan  execute programme  degonistic and commenucation scan  output scan
    29. 29. PLC conceptual applicationdiagram.
    30. 30. Sequence of PLC control When a process is controlled by a PLC it uses inputs from sensors to make decisions and update outputs to drive actuators The process is a real process that will change over time. Actuators will drive the system to new states (or modes of operation). This means that the controller is limited by the sensors available, if an input is not available, the controller will have no way to detect a condition “real time system “.
    31. 31. Number Of Scan Special I/O Time Modules Memory Communications SoftwareNumber Of AvailabilityLogical I/O Select PLC Peripherals Type Of Controller
    32. 32. Packaging Machine
    33. 33. Pick And Place Robot Control
    34. 34. swimming pool
    35. 35. sewage/water treatment
    36. 36. Chemical processing plant
    37. 37. Food/Drugs Production
    38. 38. Petrochemical ,Petrol/Gas Plant
    39. 39. Amusement Park Control
    40. 40. Scientific Experiments CERN LHC CERN built LHC 27Klm …this experiment is controlled by PLC
    41. 41. Also Martial Handling Plastic Machine Conveyor System Semi Conductors/IC Pump Control Manufacturing Paper And Pulp Industries Air Condition Control "For Glass Manufacturing Huge Sheller " Precast Concrete Generator Control System Industries Lift Control System Cement Manufacture Iron And Steel Manufacturing Printing Industries Traffic Light System Electro-plating Plants Power Stations Machine Tools
    42. 42. BUTthere is NO horizon for the Applications !!
    43. 43. PLC H.W Components: CPU =ALU +CU System Busses Memory I/O Sections Power Supply Unit Programming Device
    44. 44. Programming DeviceThe programming device is used to enter the required program into the memory of the processor.The program is DEVELOPED in the programming device and then TRANSFERRED TO MEMORY unit of the PLC.
    45. 45. CPUMicroprocessor based, allow arithmetic operations, logic operators, block memory moves, computer interface ,and local area network, functions,.. etc.CPU makes a great number of CHECK-UPS of the PLC controller itself so eventual errors would be discovered early.This is an intro to a point in next session
    46. 46. I/O SectionsInputs monitor field devices, such as switches and sensors.Outputs control other devices, such as motors, pumps, solenoid valves, and lights.
    47. 47. Power Supply UnitMost PLC controllers work either at 24 VDC or 220 VAC.Some PLC controllers have electrical supply as a separate module, while small and medium series already contain the supply module.Max current is 10mA.
    48. 48. MemorySystem (ROM) to give permanent storage for the operating system and the fixed data used by the CPU.RAM for data. This is where information is stored on the status of input and output devices and the values of timers and counters and other internal devices. EPROM for ROM’s that can be programmed and then the program made permanent.
    49. 49. Cpu
    50. 50. Von Neumann
    51. 51. System BussesThe internal paths along which the digital signals flow within the PLC are called busses.The system has four busses:  The CPU uses the DATA BUS for sending data between the different elements,  The ADDRESS BUS to send the addresses of locations for accessing stored data,  The CONTROL BUS for signals relating to internal control actions,  The SYSTEM BUS is used for communications between the I/O ports and the I/O unit.
    52. 52. Switches
    53. 53. Proximity switchInductive Capacitive
    54. 54. Sensors Feed back elements which convert the physical quantity into electrical signals Now we introduce some sensors as refreshment ,Let me go ahead ☺
    55. 55. Useful RuleIfU can measure it ,U can control itObama say if the sun light is can measure it and emamof say this is the 1st exception is provide the truth of the rule 
    56. 56. 1- Potentiometers
    57. 57. 2- Encoders
    58. 58. Incremental encoder
    59. 59. 3 -Tachometers
    60. 60. Tachometers
    61. 61. 4- Linear Variable DifferentialTransformers (LVDTs)
    62. 62. LVDTs
    63. 63. 5 - Moire Fringes
    64. 64. $5 Moire Fringes These are used in high precision applications over long distances, often meters. They can be purchased from a number of suppliers, but the cost will be high. Typical applications include Coordinate Measuring Machines (CMMs).
    65. 65. $6 Accelerometers
    66. 66. 6- Chemical pH The pH of an ionic fluid can be measured over the range from a strong base (alkaline) with pH=14, to a neutral value, pH=7, to a strong acid, pH=0. These measurements are normally made with electrodes that are in direct contact with the fluids.
    67. 67. 7 -Thermocouples
    68. 68. 8 -Resistive TemperatureDetectors (RTDs)
    69. 69. RTDs
    70. 70. 9 -Venturi Valves
    71. 71. 10-Photoelectric
    72. 72. OPPOSED
    74. 74. REFLECTION
    75. 75. IR TEMP SENSORS
    76. 76. 11- Pressure
    77. 77. Break Can u tell me which of sensors can use as position sensor in last example ?
    78. 78.  This is not all thing about sensors we can not talk about more, Coz the target is DONE ISA