Emulator 5000 training course.doc

George Brown College 2011Emulate 5000 training courseBook 1 PLC-HMITable of ContentsINTRODUCTION TO PLCs6Programmable Logic Controller6Features:6PLC compared with other control systems.7Digital and analog signals8Example9System Scale10Programming10User Interface11Communication11History12Programmable Automation Controller12DIFFERENCE BETWEEN PLC AND PAC13Inside a Programmable Logic Controller13Processor Scan14PLC14PAC14Introduction to Allen Bradley family PLC15Introduction to Emulator 500017Differences between the emulator and a physical controller17Special instructions for emulation17Start the Chassis Monitor18Create an emulator module18Create a 1789-SIM Module22INTRODUCTION TO RSLINX25Communicating with a PLC25Connecting PLCs to a computer.25So, what is RSLinx actually?25A DDE/OPC Server26Using RSLinx to up/download and monitor PLC programs.26Protocol27Create the communications driver in RSLinx Classic28Introduction to RSLogix 500032Start RSLogix 500032üProgramming Languages43Ladder Logic43Basic Bit Level programming44Ladder Logic Concepts.45Start Stop Jog logic46Number System49Memory & Data51TOD & FRD instructions53Counter54CTU: Count up54CTD: Count down55Up-down counter56Timers56TON: On delay timer57TOF: Off delay timer57RTO: Retentive timer on58Introduction to FACTORYTALK View Studio59FactoryTalk View Studio.59FactoryTalk View Studio Lab.60ADD TREND LINE74COMPARE INSTRUCTIONS81EQU Equal81The EQU instruction tests whether Source A is equal to Source B.81GRT - Greater Than82GEQ - Greater Than or Equal83LES - Less Than83LEQ - Less Than or Equal84NEQ - Not Equal85Math Instructions86ADD - Addition86SUB - Subtract86Type - Compute/Math87DIV Divide87MUL - Multiply88NEG - Negate89SQR - Square Root89CPT - Compute90Math and CTU Lab96Application Labs99COMPRESSOR99PART I99Part 299Traffic light project100PART I100Make a traffic light simulation for a 4 way intersection with the use of timers.100Batch program assignment101Part I101Part II101Celsius to Fahrenheit Lab104PART I104PART II104BSL: Bit shift left105BSR: Bit shift right108BTD: Bit field distribute110FIFO and LIFO111FIFOLab:116File Arithmetic and Logic (FAL)117FAL LAB118Add-ons instructions119Create the Add-ons program119Equipment Phase - LAB127Creating an Equipment Phase134Writing Execution code for the Resetting State136Writing Execution Code for the Running State139Writing Execution Code for the Stopping State139Test your work140Extra task: Creating the Remaining Phase states142Proportional/Integral/Derivative143Simple explanation for PID146PID Lab148Other Logic 5000 Functions155DATA TYPES & Format157The Controller File Structure-Tree Structure158TASKS -PROGRAMS-SUBROUTINES159Continuous; Periodic or Event Driven.160Produce Consume tags168Definition168Produce-Consume Lab168Import Export Tags171Export171Import172Start _ Stop lab solution from page 47174Results of exercise on page 53175INTRODUCTION TO PLCsProgrammable Logic ControllerProgrammable logic controllerDefinition (From Wikipedia, the free encyclopaedia)A Programmable Logic Controller, PLC, or Programmable Controller is a digital computer used for automation of industrial processes, such as control of machinery on factory assembly lines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory. A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result.Features:The main difference from other computers is that PLC is armoured for severe condition (dust, moisture, heat, cold, etc) and have the facility for extensive input/output (I/O) arrangements. These connect the PLC to sensors and actuators. PLCs read limit switches, analog process variables (such as temperature and pressure), and the positions of complex positioning systems. Some even use machine vision. On the actuator side, PLCs operate electric motors, pneumatic or hydraulic cylinders, magnetic relays or solenoids, or analog outputs. The input/output arrangements may be built into a simple PLC, or the PLC may have external I/O modules attached to a computer network that plugs into the PLC.PLCs were invented as replacements for automated systems that would use hundreds or thousands of relays, cam timers, and drum sequencers. Often, a single PLC can be programmed to replace thousands of relays. Programmable controllers were initially adopted by the automotive manufacturing industry, where software revision replaced the re-wiring of hard-wired control panels when production models changed.Many of the earliest PLCs expressed all decision making logic in simple ladder logic which appeared similar to electrical schematic diagrams. The electricians were quite able to trace out circuit problems with schematic diagrams using ladder logic. This program notation was chosen to reduce training demands for the existing technicians. Other early PLCs used a form of instruction list programming, based on a stack-based logic solver.The functionality of the PLC has evolved over the years to include sequential relay control, motion control, process control, distributed control systems and networking. The data handling, storage, processing power and communication capabilities of some modern PLCs are approximately equivalent to desktop computers. PLC-like programming combined with remote I/O hardware, allow a general-purpose desktop computer to overlap some PLCs in certain applications.Under the IEC 61131-3 standard, PLCs can be programmed using standards-based programming languages. A graphical programming notation called Sequential Function Charts is available on certain programmable controllers. PLC compared with other control systems.PLCs are well-adapted to a certain range of automation tasks. These are typically industrial processes in manufacturing where the cost of developing and maintaining the automation system is high relative to the total cost of the automation, and where changes to the system would be expected during its operational life. PLCs contain input and output devices compatible with industrial pilot devices and controls; little electrical design is required, and the design problem centers on expressing the desired sequence of operations in ladder logic (or function chart) notation. PLC applications are typically highly customized systems so the cost of a packaged PLC is low compared to the cost of a specific custom-built controller design. On the other hand, in the case of mass-produced goods, customized control systems are economic due to the lower cost of the components, which can be optimally chosen instead of a "generic" solution, and where the non-recurring engineering charges are spread over thousands of sales.For high volume or very simple fixed automation tasks, different techniques are used. For example, a consumer dishwasher would be controlled by an electromechanical cam timer costing only a few dollars in production quantities.A microcontroller-based design would be appropriate where hundreds or thousands of units will be produced and so the development cost (design of power supplies and input/output hardware) can be spread over many sales, and where the end-user would not need to alter the control. Automotive applications are an example; millions of units are built each year, and very few end-users alter the programming of these controllers. However, some specialty vehicles such as transit busses economically use PLCs instead of custom-designed controls, because the volumes are low and the development cost would be uneconomic.Very complex process control, such as used in the chemical industry, may require algorithms and performance beyond the capability of even high-performance PLCs. Very high-speed or precision controls may also require customized solutions; for example, aircraft flight controls.PLCs may include logic for single-variable feedback analog control loop, a "proportional, integral, derivative" or "PID controller." A PID loop could be used to control the temperature of a manufacturing process, for example. Historically PLCs were usually configured with only a few analog control loops; where processes required hundreds or thousands of loops, a distributed control system (DCS) would instead be used. However, as PLCs have become more powerful, the boundary between DCS and PLC applications has become less clear-cut.Digital and analog signalsDigital or discrete signals behave as binary switches, yielding simply an On or Off signal (1 or 0, True or False, respectively). Pushbuttons, limit switches, and photoelectric sensors are examples of devices providing a discrete signal. Discrete signals are sent using either voltage or current, where a specific range is designated as On and another as Off. For example, a PLC might use 24 V DC I/O, with values above 22 V DC representing On, values below 2VDC representing Off, and intermediate values undefined. Initially, PLCs had only discrete I/O.Analog signals are like volume controls, with a range of values between zero and full-scale. These are typically interpreted as integer values (counts) by the PLC, with various ranges of accuracy depending on the device and the number of bits available to store the data. As PLCs typically use 16-bit signed binary processors, the integer values are limited between -32,768 and +32,767. Pressure, temperature, flow, and weight are often represented by analog signals. Analog signals can use voltage or current with a magnitude proportional to the value of the process signal. For example, an analog 4-20 mA or 0 - 10 V input would be converted into an integer value of 0 32767.Current inputs are less sensitive to electrical noise (i.e. from welders or electric motor starts) than voltage inputs.ExampleAs an example, say the facility needs to store water in a tank. The water is drawn from the tank by another system, as needed and our example system must manage the water level in the tank.Using only digital signals, the PLC has two digital inputs from float switches (tank empty and tank full). The PLC uses a digital output to open and close the inlet valve into the tank.If both float switches are off (down) or only the 'tank empty' switch is on, the PLC will open the valve to let more water in. Once the 'tank full' switch is on, the PLC will automatically shut the inlet to stop the water from overflowing. If only the 'tank full' switch is on, something is wrong because once the water reaches a float switch, the switch will stay on because it is floating, thus, when both float switches are on, the tank is full. Two float switches are used to prevent a 'flutter' (a ripple or a wave) condition where any water usage activates the pump for a very short time and then deactivates for a short time, and so on, causing the system to wear out faster.An analog system might use a load cell (scale) that weighs the tank, and an adjustable (throttling) valve. The PLC could use a PID feedback loop to control the valve opening. The load cell is connected to an analog input and the valve is connected to an analog output. This system fills the tank faster when there is less water in the tank. If the water level drops rapidly, the valve can be opened wide. If water is only dripping out of the tank, the valve adjusts to slowly drip water back into the tank.In this system, to avoid 'flutter' adjustments that can wear out the valve, many PLCs incorporate "hysteresis" which essentially creates a “deadband” of activity? A technician adjusts this deadband so the valve moves only for a significant change in rate. This will in turn minimize the motion of the valve, and reduce its wear.A real system might combine approaches, using float switches and simple valves to prevent spills, and a rate sensor and rate valve to optimize refill rates. Backup and maintenance methods can make a real system very complicated.System ScaleA small PLC will have a fixed number of connections built in for inputs and outputs. Typically, expansions are available if the base model does not have enough I/O.Modular PLCs have a chassis (also called a rack) into which is placed modules with different functions. The processor and selection of I/O modules is customised for the particular application. Several racks can be administered by a single processor, and may have thousands of inputs and outputs. A special high speed serial I/O link is used so that racks can be distributed away from the processor, reducing the wiring costs for large plants.PLCs used in larger I/O systems may have peer-to-peer (P2P) communication between processors. This allows separate parts of a complex process to have individual control while allowing the subsystems to co-ordinate over the communication link. These communication links are also often used for HMI (Human-Machine Interface) devices such as keypads or PC-type workstations. Some of today's PLCs can communicate over a wide range of media including RS-485, Coaxial, and even Ethernet for I/O control at network speeds up to 100 Mbit/s.ProgrammingEarly PLCs, up to the mid-1980s, were programmed using proprietary programming panels or special-purpose programming terminals, which often had dedicated function keys representing the various logical elements of PLC programs. Programs were stored on cassette tape cartridges. Facilities for printing and documentation were very minimal due to lack of memory capacity. More recently, PLC programs are typically written in a special application on a personal computer, then downloaded by a direct-connection cable or over a network to the PLC. The very oldest PLCs used non-volatile magnetic core memory but now the program is stored in the PLC either in battery-backed-up RAM or some other non-volatile flash memory.Early PLCs were designed to be used by electricians who would learn PLC programming on the job. These PLCs were programmed in "ladder logic", which strongly resembles a schematic diagram of relay logic. Modern PLCs can be programmed in a variety of ways, from ladder logic to more traditional programming languages such as BASIC and C. Another method is State Logic, a Very High Level Programming Language designed to program