Hello friends, How are you doing? Today, we have a very interesting topic of PLC ladder programming which is how to detect the transition between true and false and from low to high?. I know you are asking why do we need that? Well! Imagine my friends, we want to start a motor when the input signal state changes from high to low or from false to true. Let us give two examples to highlight the edge detection techniques. Good examples of using edge detection-based logic are timers and counters. In counters, they are energized to count up or down when a signal appears and the same for timers. Figure 1 shows the difference between using the edge to control a motor. In the top part, the motor is controlled by an input switch. the output is ON and OFF b ...
Hello friends, I hope you all are fine and enjoying good health. Today's tutorial, as the name shows, is on Introduction to PLC. PLC is an abbreviation of Programmable Logic Controller. Recently I worked on a project in which I have to design a Automated coffee Mixing Machine Using PLC. It worked quite good and I had a great time while working on it. After completing that project, it occurred to me that I haven't posted any tutorial on PLC. So I thought of starting this tutorial. This tutorial is not gonna cover in single post so my plan is to divide it in parts.
Today. I am gonna give an overview about PLC. We will have a look on basics i.e. what is PLC? Why we use PLC instead of microcontroller like Arduino or PIC Microcontroller? What's its adv ...
Hello friends! We hope you are very well! Today we are here for complementing our knowledge with one of the most important topics in PLC programming and practice its implementation in PLC ladder logic programming. Our topic today is about counters which help us to know the production size at any time, the repetition of specific tasks and events. Many real-life situation problems need counter like garage capacity should be tracked by using counters to report how many cars are inside and if there is room for incoming cars or it's full. Another critical problem is to count the repetitive tasks and events in manufacturing. Furthermore, counting products and pieces for taking an action like performing maintenance, stop operation, turn over to next prod ...
Hi friends. Today we are going to go through one of the most commonly used topics in writing ladder logic programming which is using comparator operations. This includes the logical and mathematical comparison between variables to decide where the logic goes.
There are many comparator operations like equal (==), not equal (<>), less than (<), greater than (>), less than or equal (<=), greater than or equal (>=). All these comparator operations might be used in different logic scenarios while writing a ladder logic program. In this tutorial, we are going to go over each operator showing the input operators and output as well. In addition, we will practice some examples with the simulator to familiarize how to use them flexibly whi ...
Hello friends, I hope you all are fine. Today, we are starting a new tutorials series on Ladder Logic Programming, used in PLC. It's our first tutorial in this series, so we are going to have a look at the detailed introduction to PLC and ladder logic. After welcoming every one of engineers, technicians, students, and hobbyists who have come to read this article willing to learn PLC programming, I would like to introduce one of the most used programming languages of PLC. The language we introduce here is a visualized language that connects and combines graphical symbols in logical flow same as the way we wire electrical circuits and that is the secret behind its simplicity not only in implementation but also in diagnosing problems.
Ladder Logic Pro ...
Hello friends, all of us know that PLCs are nothing but the smartest migration from relay logic control to programmable logic control. Also, you know clearly that, logic is the heart of any programming language, and the same is applied to ladder logic programming. Bitwise operators represent the logical operations including the basic logical operations like AND, OR, and NOT and the derived logical operations like NAND, NOR, and XOR. in most cases, for each bitwise operator, there are inputs based on which the output can be decided. Some of these bitwise operators have two inputs and some have only one input. In this article, we are going to present how we can use these bitwise logical operators and their instructions with examples and practice using the PLC simulator.
Logic Gates ba ...
Hey guys! hope you are all very well. Today I come to you with a new process to learn, program, and simulate for practicing ladder logic more and more. The process we are going to implement today is a very common process that could be there in many many industries which is a silo process that aims to automate the process of filling containers or bottles with a liquid. Figure 1 shows the complete scene of the process including the system components, switches, indicators, sensors, and actuators that are integrated to make the system operate. Briefly and before going into deep details, let’s state what the system does and how it operates. Well! The system automatically fills the boxes that are traveling on the conveyor which is driven by a motor. They are filled with a liquid stored in the si ...
Hi friends, today we are going to explore mathematical computations in ladder logic. Like in any programing language you should find logic and mathematic computations, here in PLC programming you often need to process the input data that is collected from reading analog devices like temperature, level, flow et cetera. Then you need to run some calculations on this data to derive some other variables for deciding to run or stop some device or even to determine analog output to output to analog device i.e. valve or actuators. In the following sections, we are going to explore the mathematical functions and their input operators and outputs as well. Then we will show how to utilize such functions in ladder logic with simple examples and as usual enjoy practicing them thanks to the PLC simula ...
Hello friends! I hope you are all very well! I am so happy to meet you today to continue learning and practicing PLC ladder logic programming. In an earlier part, we already have gone through the very basic logic gates of “AND”. “OR”, and “NOT”. Today we are going to resume the simulation of logic gates. We have started and gone through simulating the basic logic gates which are “AND”, “OR”, and “NOT” as they are the most important basic logic gates by which we can form other logic gates. However, because the logic of large-scale projects is getting more and more complicating, a lot of time we have to use the other functions to do tasks faster. For example, we have shown in the logic gates article that, XOR can be used to compare two inputs and ch ...
Hi friends, how are you doing? Today will integrate all of what we have learned so far in this series to build the first project based on ladder logic programming. Because we all are interested in industry, we pick one industrial project, Bottle Filling and Capping Projects, which is very common today. The problem we are going to solve today is bottle filling and capping. We have learned all basics of ladder logic including contacts and coils operation, logic gates, rising and falling edges, timers, and counters. So, today we will utilize all of these components to implement a complete ladder program of filling and capping problems.
Operation and Logic of Bottle Filling and Capping Process
For simplifying the operation of the process of filling and capping, fig. 1 shows the process flow ...
