Industrial Automation Engineering Manual PDF

1 TABLE OF CONTENTSNG MANUAL TABLE OF CONTENTS CHAPTER 1: INTRODUCTION TO INDUSTRIAL AUTOMATION 1.1 OVERVIEW OF INDUSTRIAL AUTOMATION SYSTEM 1.2 BUILDING BLOCKS OF PROCESS AUTOMATION CHAP...

1 TABLE OF CONTENTSNG MANUAL TABLE OF CONTENTS CHAPTER 1: INTRODUCTION TO INDUSTRIAL AUTOMATION 1.1 OVERVIEW OF INDUSTRIAL AUTOMATION SYSTEM 1.2 BUILDING BLOCKS OF PROCESS AUTOMATION CHAPTER 2: FIELD DEVICES AND INSTRUMENTS 2.1 SENSORS: 2.1.1 PUSH BUTTON 2.1.2 EMERGENCY PUSH BUTTON 2.1.3 SWITCHES 2.1.4 PROXIMITY SENSORS 2.1.5 LEVEL TRANSMITTER 2.1.6 PRESSURE TRANSMITTER 2.2 ACTUATORS 2.2.1 VALVES CHAPTER 3: COMMUNICATION PROTOCOLS 3.1 NEED FOR COMMUNICATION PROTOCOLS 3.2 COMMON COMMUNICATION PROTOCOLS: 3.2.1 MODBUS RTU PROTOCOL 3.2.2 MODBUS TCP/IP PROTOCOL 3.2.3 OPC UA PROTOCOL CHAPTER 4: PLC AND DRIVES 4.1 PROGRAMMABLE LOGIC CONTROLLERS (PLC): 4.1.1 DEFINITION AND ROLE IN AUTOMATION. 4.1.2 BASIC STRUCTURE OF A PLC 4.2 VARIABLE FREQUENCY DRIVES (VFDS) 4.3 BASICS OF PLC PROGRAMMING: 4.3.1 BASIC LADDER LOGIC ELEMENTS 4.3.2 SIMPLE PLC PROGRAM EXAMPLES WITH FIELD DEVICES. General  2 CHAPTER 5: SUPERVISORY LEVEL (HMI) 5.1 INTRODUCTION TO HMI 5.2 COMMON HMI FUNCTIONS 5.3 BASICS OF HMI PROGRAMMING General  3 Chapter 1 Introduction to Industrial Automation In this Chapter Learn about What is Industrial automation (process) Open loop and closed loop control systems Sensors, actuators, controllers, transmitters 1.1 Overview of industrial automation systems and their components Imagine a factory floor buzzing with activity, but instead of just people, there are robots and smart machines working alongside them. That's the power of industrial automation! This technology integrates computers, robots, and sensors to streamline and optimize manufacturing processes. In short, it's about using technology to make things faster, better, and safer. Think of the system like a team. Sensors act as the eyes and ears, constantly gathering information like temperature or pressure. Communication protocols are like a shared language, allowing all the devices to talk to each other. The PLC, the brain of the operation, receives data from sensors, makes decisions based on its program, and sends instructions. Finally, actuators, the muscles, translate those instructions into actions like opening valves or moving robots. By working together, this team transforms manufacturing! Get ready to dive deeper into each of these components in the following chapters. 1.2 Building blocks of process automation 1.2.1 SENSORS/TRANSDUCERS A sensor is a device that converts a physical quantity from the environment (like temperature, pressure, light, or motion) into an electrical signal that a control system can understand. EXAMPLES: Temperature sensor, pressure sensor, light sensor, proximity sensor, microphone, camera. INPUT: Physical quantity (Pressure, Temperature, level, flow etc) General  4 1.2.2 TRANSMITTERS A transmitter converts physical process variables like temperature, pressure, flow, and level into standardized electrical signals. These signals are then processed by control systems to regulate and optimize industrial processes. In essence, transmitters provide the essential feedback loop for automated control and monitoring. EXAMPLES: Level transmitter, pressure transmitter, etc. INPUT: Response signal from the sensor. 1.2.3 CONTROLLER A controller is a programmable electronic device that continuously monitors and controls industrial processes. It acquires data from sensors, processes information according to programmed logic, and sends output signals to actuators to regulate system behaviour. It regulates a process by continuously comparing a measured variable (Process Variable) to a desired set-point and sending signals. EXAMPLES: Programmable Logic Controller, Distributed control system INPUT: standard 1 to 5 V signal or 4-20 mA signal from Transmitter General  5 1.2.4 ACTUATORS An actuator is a device that receives an electrical signal from a control system and performs a physical action in the real world. Examples: Motor (controls speed and direction), solenoid valve (controls fluid flow), relay (switches circuits on/off), speaker (produces sound). Input: Electrical signal from a control system Set Point Actuator Controller Process variable Process Sensors Transmitter This setup is an example of above closed loop system observe all the components used. A flow transmitter measures the rate of fluid flowing through a pipe and converts this measurement into an electrical signal. This signal is sent to a control system which compares the measured flow rate to a desired setpoint. The control system then generates an output signal to adjust a control valve, increasing or decreasing the flow General  6 rate to maintain the desired flow conditions. This closed-loop system ensures that the fluid flow is regulated and controlled according to the specified setpoint. Exercise: Identify the building blocks of process automation used here. General  7 Chapter 2 Field devices and instruments In this Chapter Learn about Various sensors used in industrial automation and their applications. 2.1 SENSORS Automation is the future, no doubt. Among the various components of automation, sensors make up an important part. Look around! and you will see how sensors surround us. Detecting fire or smoke, turning on lights by detecting your presence, opening garage doors as soon as the car is in front of the gate, and adjusting room temperature, have all become common parts of our lives, and all these take place with the help of sensors. what are different types of sensors used? Let’s find out. 2.1.1 PUSH BUTTONS Push buttons are power-controlling switches of a machine or appliance. In electric circuits, the power flows continuously through the devices, and to regulate this power supply, we use push buttons. General  8 2.1.2 EMERGENCY PUSH BUTTON The emergency stop push button serves as a safety measure during critical situations. Once pressed, the emergency stop push button will immediately cut off the flow of electricity to the machinery, ensuring immediate safety for both operators and machinery during an emergency shutdown situation. 2.1.3 SWITCHES Normally Open (NO) and Normally Closed (NC) describe switch positions. An NO switch is like a light switch - off (open) when at rest, and on (closed) when pressed. An NC switch is the opposite - on (closed) at rest and opens (off) when triggered. I. Selector switch A selector switch can control on or off for different currents circuit by rotating the handle. General  9 Types: Two-State Selector Switch: This is the simplest type. It has only two possible positions or options like turning a light on or off. Three-State Selector Switch: This type gives you three options to choose from. It's like a traffic light with red, yellow, and green. Example: A ventilation system 1. Position 1 (Off): Disconnects power from the ventilation fan, turning it off. 2. Position 2 (Low): Connects power to the fan at a lower voltage, providing low airflow for basic ventilation. 3. Position 3 (High): Connects power to the fan at full voltage, providing high airflow for tasks like dust extraction or rapid cooling. This allows the operator to manually select the appropriate ventilation level based on the specific needs of the process. ii. Level switch A Level switch is the sensor that used to detect the Presence of the Liquid, powder or granulated material at specific location. When electrode is in contact with the conductive liquid, the circuit closes due to the conductive fluid completing the circuit. Relay operates and the level indicator will glow a. Point level sensor Point level measurement sensors are used to detect whether a material is present or absent at a specific point in a container they don't provide continuous level readings, but rather a binary output (on/off) indicating if the material has reached a predetermined level. Application: Container Level Monitoring General  10 These sensors are commonly used for container level monitoring, applicable to tanks, silos, hoppers, or any vessel holding liquids, powders, or bulk materials. A point level sensor can be installed at a critical level within the container, such as high level or low level. When the material reaches the sensor's point, it triggers a signal (usually an electrical switch turning on/off) b. Continuous level sensor Continuous level sensors provide real-time and continuous measurement of the level of liquids, slurries, or bulk solids within a container. Unlike point-level sensors which offer a binary on/off signal, these sensors offer a continuous output proportional to the actual level. 2.1.4 PROXIMITY SENSORS A proximity sensor is a non-contact device that detects the presence of an item when it enters its sensory field. Depending on the type of proximity sensor, the sensor may detect a target via sound, light, infrared radiation (IR), or electromagnetic fields. A proximity sensor frequently generates an electromagnetic field or a beam of electromagnetic radiation to detect changes in the electromagnetic field or return signal. TYPES OF PROXIMITY SENSORS A PPLICATION detecting metal objects on conveyor belts, Inductive monitoring machine tool position, automatic door opening Detecting non-metallic objects (plastic, wood) on Capacitive assembly lines, level control of liquids or bulk materials, presence detection in touchless switches Touchscreens in smartphones and tablets, Resistive detecting liquid level (simple approach), wear and tear monitoring in machinery (limited use) Automatic hand dryers, intrusion detection IR Proximity systems, obstacle avoidance in robots. General  11 2.1.5 LEVEL TRANSMITTER Continuously measures the level of material and provides a proportional electrical signal that reflects the fill level. Example: Ultrasonic level Transmitter Ultrasonic level transmitters are primarily used for determining the level of substance within tanks or vessels. By emitting sound waves and measuring the time it takes for the echoes to return, these devices accurately gauge liquid heights. They are widely employed in industries requiring precise liquid level monitoring for process control and optimization. 2.1.6 PRESSURE TRANSMITTER Pressure transmitters convert the mechanical pressure into an analog electrical signal. measure pressure in various mediums (liquids, fluids, gases) Example: measuring process pressure with a range of 0-100 psi. The sensor/transducer performs the initial measurement and converts it to an electrical signal of 0-3 mV. The transmitter then converts that signal to a standard signal of 1-5 V, which is received by a PLC analog input module. General  12 2.2 ACTUATORS Actuators are devices that convert control signals (electrical, pneumatic, hydraulic) into mechanical motion or force. They act as the final control element, receiving instructions from the controller and translating them into physical manipulation of the process. This manipulation can involve opening/closing valves, adjusting pump speed, or positioning dampers, directly affecting factors like flow rate, pressure, or temperature. what are the different types of Actuators used? Let’s find out. TYPES OF ACTUATORS WORKING ELECTRICAL Converts electrical signals into linear or rotary motion PNEUMATIC Uses compressed air to generate force and movement for pushing, pulling, or rotating. HYDRAULIC Uses hydraulic power to produce mechanical motion 2.2.1 VALVES Valves control fluid flow in industrial systems, ensuring safety, efficiency, and product quality by regulating, isolating, and directing fluids as needed. Examples: Knife edge valves, ball valves, and Solenoid valves. General  13 General  14 Chapter 3 Communication protocols In this Chapter Learn about Various protocols used between devices. Basic understanding of protocols and their need 3.1 NEED FOR COMMUNICATION PROTOCOLS A protocol is essentially a set of rules or standards that govern communication between devices. Just like people follow specific social norms when conversing, devices adhere to protocols to understand and exchange information effectively. In industrial settings, protocols like Modbus and OPC UA ensure that various machines, sensors, and controllers can communicate seamlessly, enabling efficient data exchange and control, which is crucial for modern automation systems. 3.2 INTRODUCTION Physical layer:the fundamental building block of any network. It defines the electrical, mechanical, procedural, and functional specifications for establishing, maintaining, and terminating physical connections between network devices. In essence, it's the hardware component that enables the transmission of raw bits (binary data) over a physical medium. Protocols: provide the intelligence that enables devices to communicate effectively over the physical infrastructure provided by the physical layer. They ensure that data is formatted, transmitted, and interpreted correctly. master-slave concept: one device (the master) controls the actions of other devices (the slaves). The master sends commands to the slaves, and the slaves carry out those commands. This is a common architecture in many systems, including industrial control, home automation, and networking. 3.2.1 MODBUS RTU PROTOCOL Modbus RTU uses serial communication for data exchange between a master and multiple slaves. It's simpler but slower, suitable for shorter distances. General  15 Example: In a small water treatment plant, Modbus RTU can connect multiple sensors and actuators along a single serial communication line. For instance, a master PLC can communicate with pH sensors, flow meters, and control valves using RS-485, a communication standard used in industrial environments to connect multiple devices over long distances, allowing information to be shared between machines reliably and efficiently. This setup is suitable for smaller-scale operations where devices are physically close. Important Points about RS-232 and RS-485 An RS232 Serial Interface is for connecting two devices. There will be one transmitter and one receiver. An RS485 Serial interface can connect up to 32 devices to a single transmitter. The maximum operational distance between a transmitter and a receiver for RS232 is 15 Meters. However, the length can be extended considerably with a trade-off with slower data rates. For RS485, the distance is remarkably long of up to 1200 Meters. That’s 24 times the distance of RS232. It will only be reasonable to pick RS485 if the equipment is meant to operate at a distance from the transmitter. 3.2.2 MODBUS TCP/IP Modbus TCP (Transmission control protocol) uses Ethernet for faster communication, allowing more devices and longer distances. General  16 Example: In a larger water treatment facility, Modbus TCP can be employed to connect various subsystems across a plant. For example, a central SCADA system can communicate with multiple PLCs in different plant areas over an Ethernet network. (SCADA stands for Supervisory Control and Data Acquisition. A central computer system monitors and controls industrial processes like a factory or power plant. It gathers information from machines, displays it, and allows operators to control them from one place.) COMPARISON: Parameter Modbus RTU Modbus TCP Physical Layer Serial (RS-232, RS-485) Ethernet Network Topology Master-slave Master-slave Data Transmission Asynchronous, serial Packets over TCP/IP Error Detections Cyclic Redundancy Check TCP checksum Addressing Unique slave addresses IP address and port (0-247) number (default 502) Data Format Binary Binary encapsulated in TCP/IP packets Maximum Nodes Typically, 32 Theoretically unlimited (depends on network infrastructure) Data Rate Lower (depends on baud Higher (depends on rate) Ethernet network speed) General  17 3.2.3 OPC UA PROTOCOL The OPC UA framework supports the client/server services and protocols and publish/subscribe (Pub-Sub) models and protocols. OPC UA can run in a dedicated client-server relationship. In the Pub-Sub scenario, the server sends (publishes) data to the network, and the client (who subscribed) will receive the data. OPC UA not only transfers machine information such as set-points, measured values, and process parameters, but it also defines and describes the data. This is done through mappings in the OPC UA specification. Imagine a factory with machines from different companies. Each might speak a different "machine language." OPC UA acts as a translator, letting them all understand each other. This makes it easier to share information, like temperature, pressure, or speed, between different machines and computers. General  18 Chapter 4 PLC and Drives In this Chapter Learn about Role of PLC in automation Basics of ladder logic programming Integrating field devices with PLC 4.1 PROGRAMMABLE LOGIC CONTROLLERS 4.1.1 DEFINITION AND ROLE IN AUTOMATION A Programmable Logic Controller (PLC) is an industrial computer designed to automate processes. It is equipped with ruggedized hardware and software to reliably control machinery and equipment in manufacturing, production, and other industrial settings. PLCs receive input signals from sensors, process this data according to programmed logic, and generate output signals to control actuators, thereby automating and optimizing industrial operations. 4.1.2 BASIC STRUCTURE OF PLC POWER SUPPLY PROCESSOR MODULE CENTRAL PROCESSING UNIT INPUT OUTPUT MODULE MEMORY MODULE PROGRAM DATA PROGRAMMING DEVICE General  19 ✓ Processor: The "brain" of the PLC, responsible for executing control logic and managing system operations. ✓ Power Supply: Provides electrical energy to the PLC and its components. First supply current goes to the power supply machine which is 220v AC, later it is divided into three parts and converts it from AC to DC. ✓ Memory: Stores the PLC program, system data, and input/output information. ✓ Communication Interface: Facilitates communication with other devices, systems, and networks. ✓ Input Modules: Receive signals from sensors and convert them into a format understandable by the PLC. ✓ Output Modules: Convert PLC signals into control actions for actuators like motors, valves, and relays. The input and output module takes 24v DC. This part can continue in a loop cyclically. For one single cycle, this whole process is called the scan time of PLC. 4.2 VARIABLE FREQUENCY DRIVES A variable speed drive is an electronic device used to control the speed and torque of an electric motor by varying the frequency and voltage of the power supplied to it. It is also known as a (VFD) variable frequency drive or adjustable speed drive (ASD). General  20 Application: A VFD can be used to control the speed of a pump in a water supply system. By adjusting the pump's speed, the VFD can precisely regulate the water flow rate to match varying demands. This is crucial in applications like municipal water supply, where water consumption fluctuates throughout the day. 4.3 PROGRAMMING AND SOFTWARE This section introduces you to Programmable Logic Controllers (PLCs) and ladder logic programming. We'll explore the IEC 61131-3 standard, a common language for PLC programs. Using the M580 PLC and its Control Expert software, you'll learn to build control programs with ladder logic elements. Complete all the activities in this section with the help of the instructions provided. General  21 4.3.1 BASIC LADDER LOGIC ELEMENTS Activity 1-Basic contacts and coils used in ladder logic In this activity Learn about Ladder logic contacts. Ladder logic coils. Contacts and coils are the elementary objects of ladder logic. They are discrete programming elements that deal with Boolean states ‘0’ or ‘1’. In this activity, you will learn about How to configure Normally open contacts, normally closed contacts, Coils, and Negated coils. Understanding Logic: Ladder logic is a programming method that uses a graphical diagram inspired by electrical relay circuits. The diagram consists of two vertical lines (rails) and horizontal lines (rungs), forming a ladder-like structure. This visual representation is called a ladder logic diagram (LLD). The left rail is connected to the input switch/contact and the right rail is connected to the output coil. and the switch and coils are connected through a wire. Normally open contact is open when not actuated, it closes the circuit when pressed or activated, allowing current flow. A Normally closed contact is closed when not actuated, it opens the circuit when pressed or activated, stopping the current flow. Output devices are devices such as motors, valves, indicators, lights, etc represented using the coil. Contact Coil Rung s Rails General  22 Let’s get started! 1. Create a new section in Ladder logic a. Open the project created “Training”. b. Create a new section under the MAST task using the LD language and name the section Contacts coils. Click OK 2. A new section that’s created should look like this General  23 3. Configure the Normally open contacts and coils a. Locate the LD editor toolbar. From this toolbar insert the normally open contact into the section b. Insert Coil from the toolbar into the section. Use the horizontal Boolean connection to connect the contact and coil c. Assign a variable to the contact by double-clicking on it. General  24 Click OK d. Create variable as prompted. Click on e. Insert a coil from the LD editor into the section, as shown. General  25 f. To Assign a variable to the coil, create a variable as prompted. Save the project 4. Configure the Normally closed contacts and coil a. Locate the LD editor toolbar. From this toolbar insert a Normally closed contact and coil into the section as shown General  26 b. Assign Variables to contact and coil as shown. Save the project. 5. Configure the Normally open contact and negated coil a. Locate the LD editor toolbar. From this toolbar insert a Normally open contact and Negated coil into the section General  27 b. Assign variables to the contact and coil as shown. Save the project. 6. Build and transfer the program into the simulator, run the controller a. Build the Project by clicking on the below icon in LD editor. General  28 Choose simulation mode and connect the PLC Transfer Project to PLC and click on Run The section should look like this. General  29 7. Animation Table and Testing the program b. Right click on the contact and initialize animation table. Note: You can also assign the Boolean values by clicking on set value Repeat the process by initializing animation table for all variables c. Animation Table General  30 d. Modify and try various input combinations for variables by clicking on Modification Exercise: Observe the Output value for different input values and develop a truth table. General  31 Activity 2-Programming basic logic gates In this activity: Programming logic gates AND, OR, NOT, XOR using ladder logic. Logic gates (AND, OR etc.) are the building blocks of digital circuits. Ladder logic, a graphical language for industrial control, can mimic these gates using contacts and coils (outputs) to create desired control functions. 1.AND 2. OR A B Y A B Y 0 0 0 0 0 0 0 1 0 0 1 1 1 0 0 1 0 1 1 1 1 1 1 1 3.XOR 4.NOR A B Y A B Y 0 0 0 0 0 1 0 1 1 0 1 0 1 0 1 1 0 0 1 1 0 1 1 0 1. Create a new section in Ladder logic a. Open the project created “Training”. General  32 b. Create a new section under the MAST task using the LD language and name the section Logic gates. Click OK 2. New section created should look like this. General  33 3. Configure the Normally open contacts and coils to create AND logic a. Locate the LD editor toolbar. From this toolbar insert normally open contacts and coils as shown, b. Assign variables to the contacts and coil by double clicking on them. Click OK c. Create variable as prompted by Click on The section should like this. General  34 d. Add comments to the program as shown. e. configure the Normally open contacts and coils as shown, to create OR logic. General  35 f. Assign variables to the contacts by double-clicking on them and choose the inputs created for the previous AND logic from the drop-down. Click OK Assign Variable to the output coil and create new variable as prompted. Click On General  36 Add comments to the section. Note: Arrange spaces between your rungs in the section by right-clicking on the rows and columns to get insert rows and columns option. g. configure the Normally open contacts and coils as shown, to create XOR logic. General  37 h. Assign Variable to the contacts from the previously created input values Add comments to the section. I. Configure contacts and coils for creating NOR logic. General  38 Assign variables from the previously created inputs for all the logics and create. new output variable Output_Y4. add comments to the section. 4. Build and transfer the program into simulator, run the controller a. Build the Project by clicking on the below icon in LD editor. Choose simulation mode and connect the PLC. General  39 Transfer project to PLC and click on Run General  40 Click on Transfer The section should look like this. 5. Animation Table and Testing the program b. Right click on the contact and initialize animation table. Repeat the same process for all the variables. General  41 b. Modify and try various input combinations for variables by clicking on Modification. Observe the Output value for different input values. Exercise: Try to write ladder logic program for NOT, NAND and XNOR logic! General  42 Activity 3-Programming using Predefined blocks. In this activity: Learn how to use operator, comparator used in ladder logic. Learn how to use ON delay, OFF delay timers. Consider a scenario where a conveyor belt needs to activate only when a box is present AND a safety gate is closed. Operator helps in checking that condition using AND operation between both the variables. A comparator then checks if the bottle is within the correct height range with the help of value obtained from sensor. If all conditions are met (operators) and the bottle height is correct (comparator), the machine fills the bottle! 1. Create a new section in Ladder logic a. Open the project created “Training”. b. Create a new section under the MAST task using the LD language and name the section Predefined blocks. c. The section should look like this. 2. Configure the operator block a. Locate the LD editor toolbar. From this toolbar insert Operator block as shown General  43 b. Double click on operator block and enter the expression: outputY1: = Input_A & Input_B. 3. Configure the Comparator block a. Locate the LD editor toolbar. From this toolbar insert comparator and coil b. Double click on comparator block and enter the expression: Input1>input2 Note: Create the variables input1 and input2 in the elementary Variables and select the type as INT. General  44 c. Double click on coil to assign Output variable as prompted. 4. Build and transfer the program into simulator, run the controller a. Build the Project by clicking on the below icon in LD editor. Choose simulation mode and connect the PLC. General  45 Transfer project to PLC and click on Run 5. Animation Table and Testing the program b. Right click on the contact and initialize animation table. Repeat the same for all the variables General  46 b. Modify and try various input combinations for variables by clicking on Modification. Exercise: why is there no coil after operator block, can we add it? Explore various programs where these blocks can be used. ON delay timers: They hold off starting a machine (like a conveyor) for a preset time, ensuring things are ready before continuing. Even after start command is given only after the time, we set the process starts. OFF delay timers: They keep a machine running (like a cooling fan) for a short while even after the stop signal (like turning off the oven), preventing abrupt shutdowns and potential damage. General  47 1. Create a new section in Ladder logic d. Open the project created “Training”. e. Create a new section under the MAST task using the LD language and name the section Timers. f. The section should look like this. 2. Configuring Timers a. Locate TON from the TIME section in toolbar. b. Insert coil and contact as shown. General  48 3. Assign variables to the coil and contacts as shown from the previously created inputs Click on the PT (preset value) input of Timer and enter vale t#5s Introducing on delay of 5 seconds 4. Build and transfer the program into the simulator, run the controller a. Build the Project by clicking on the below icon in the LD editor. General  49 Choose simulation mode and connect the PLC. Transfer project to PLC and click on Run Click on Transfer Confirm run The section should like this General  50 Observe the delay for the output to turn on Exercise : Try programming using OFF-delay timer and observe the difference in application of both the timers in industries,list down few applications General  51 4.3.2 SIMPLE PROGRAMS USING FIELD DEVICES Activity 1-Output on/off (Lamp) using single push button. In this activity: Learn about Push button and its applications Programming simple Lamp on/off with push button using Boolean instructions Logic: This function is also called push on push off logic sometimes even flipflop or toggle function. It is the same function as the on/off button on your computer or mobile phone. When you push the button the first time, the output will be activated. Now, when you push the button for the second time, the output will deactivate and turn off. The single push button has two functions: on and off. Scenario: Imagine a lamp connected to a PLC. We want to control this lamp with a single push button. Here's the catch: 1. Pressing the button once turns the lamp ON. 2. Releasing the button doesn't turn lamp off 1. Create a section in ladder logic a. Create a new project and name it training. b. Create a new section under MAST task using LD language, and name the section Pushbutton General  52 Click OK c. The new section created should look like this 2. Configure the contacts, coils and assign variables a. Locate the LD editor toolbar From this toolbar insert normally open contact into the section b. Locate and select coil from LD editor and insert into the section General  53 a. Assign variable as shown to the contact by double clicking on them Create variable as prompted Click on Similarly assign M0 variable to the coil Variable Purpose Push button Contact to give input /press push button M0 Memory coil to store the status that input is enabled d. Insert two more normally open contacts and coil as shown into the section Insert Horizontal and vertical Boolean connections and if any unwanted links are created, right click on the link and click on delete General  54 e. Assign variables as shown to the contact and coil by double clicking on them Follow the previous steps to create variables as prompted. Note: all variables are Boolean Note: This way of adding output in parallel to input is called Latching. Latching is useful for situations where you want something to stay on until specifically turned off. Examples 1.Keeping a machine running after a start button is pressed (conveyor belt) 2.Holding an alarm signal on until acknowledged by an operator. General  55 Variable Purpose Bulb on Using the M0 coil status as command to turn on the bulb on 3. Simulation Build and transfer the program into the simulator and run the controller. Observe the output turned on even after we set the value for pressing pushbutton as 0. Exercise: Explore where else in programming can we apply concept of latching General  56 Activity 2- Tank filling using level switch. In this activity: Learn how to Program Tank filling based on level reached. Use Basic ladder logic elements and concepts learnt in previous sections. This scenario aims to demonstrate the control of liquid flow based on pre-defined level thresholds using ladder logic programming. The pump should be OFF initially. start filling the tank when the liquid level is below the low-level sensor. stop filling the tank once the liquid level reaches the high-level sensor. How will you program this? Ladder logic Program: I/O variables used: Start fill Command to start filling the tank Stop fill Command to stop filling the tank M1 Memory bit to save the status Low-level Lower-level set in tank High-level Higher-level set-in tank Valve open Command to open Valve General  57 Chapter 5 Supervisory Level (HMI) In this Chapter Learn about What is HMI? Basics of HMI designing Integrating PLC with HMI 5.1 INTRODUCTION TO HMI An HMI, or Human Machine Interface, is like a user-friendly control panel. You've probably seen them as touchscreens on ATMs, vending machines, or microwave ovens. In industries, HMIs are crucial for operators to monitor and control complex machinery. Imagine a power plant; without an HMI, operators would have to manually check countless gauges and valves. An HMI provides a clear, visual display of all essential information, allowing operators to make informed decisions quickly, preventing errors, and boosting efficiency. Additionally, HMIs act as early warning systems, alerting operators to potential problems through alarms, like a fire alarm signalling danger. 5.2 COMMON HMI FUNCTIONS Data Acquisition and Display Display live process data (temperature, pressure, etc.) Visualize data with graphs, charts, and gauges. Log historical process data for analysis Process Control Adjust setpoints to achieve desired outcomes. Implement automatic control loops. Manually override control in emergencies Alarm and Event Management Trigger alarms based on process deviations. Prioritize alarms based on severity. Log process events for troubleshooting Operator Interface General  58 Authenticate users with logins and passwords. Provide intuitive menu navigation. Data Communication Interface with PLCs to exchange data. Enable remote monitoring and control. Reporting and Analysis Generate reports and statistics. Analyse process trends and patterns Track key performance indicators (KPIs) Complete all the activities in the following section with help of instructions provided. General  59 5.3 BASICS OF HMI DESIGNING Activity 1- Integrating PLC with HMI In this activity Learn about How to use variables created in PLC in HMI How to design a basic HMI screen In the Activity 1 from section 4.3.2, we learnt how to program a push button using PLC programming. Now let’s try developing a simple HMI screen with symbols and variables for operating the logic using Vijeo designer tool. 1. Create a new Project a. Click on file and select new project. Click Next General  60 b. The screen looks like this. c. Right Click on I/O Manager >>New driver>>Modbus TCP/IP General  61 d. Configure IP Address for simulation. Select the checkbox for IEC61131 Syntax e. Right click on Variables>>Link variables General  62 f. Choose the PLC program you created by selecting files of type. STU General  63 2. Select variables used in the PLC program a. Choose the PLC program you created by selecting files of type. STU b. Insert a Switch symbol from the tool. In the program, Pushbutton is a Boolean logic that chooses bit operation and assigns a variable. General  64 c. Choose the Lamp symbol from the toolbar and assign its operation. d. You can choose the symbol from various options available. General  65 3. Build and simulate the Project Exercise: what is the Connection we used between HMI and PLC explore other methods as well Explore various functions such as numeric display by following similar procedure of assigning variables from available Tags. General