Hello friends, after completing that basic part of ladder logic programming, let us today go through one topic which is not essential to know to complete a PLC ladder program but it is important t have our code readable program and reusable pieces of code. That could happen by using what so-called a subroutine. So what is a subroutine? Well, it is a piece of code that includes a few rungs to perform specific tasks. that piece of code can be reused numerous times through the program when we need to call it for performing that task. That subroutine enables us to structure our code like building blocks so that the program will be readable very easy and also reusable later in other projects. The idea of dividing the program into routines to apply the divide and conquer technique is very crucia ...
Hi friends, I hope you are very well; today in this tutorial, we will practice conditional jumping for performing some code at the occurrence of some conditions. Like any other programming language, jumping is one of the most common approaches to transfer the execution from its sequential mode to run different processes or instructions marked by a label and bypassing the lines of codes in between the last executed transaction before the jump instruction and the labeled instruction whom the program is going to move to. The good thing about this technique is shortening the scan cycle of the program due to not running the whole program. However, using jumping techniques in coding is very dangerous. It would help if you were careful of missing some op ...
In the previous post Logical Gates in Ladder Logic for PLC, we had an overview of what is Ladder Logic programming and we have also implemented three basic Logical gates in Ladder Logic form. Today, we are gonna have a look at some complex Logical Gates in Ladder Logic for PLC. So, I hope till now you guys have basic knowledge of Ladder Logic and can implement complex logical gates in it. If you haven't read the previous post then must read because without that knowledge you won't understand this post.
In today's post we are gonna implement few complex logical gates. Its not gonna be much difficult if you have the basic concepts. I am just pointing out few important points here. While implementing any gate in ladder logic, always consider rung as ...
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 ...
Hi friends and hope you are all very well. Today, we are going to deal with one of the most important and common problems that would be there in everyday tasks in industry and its solution. The problem is the safety of equipment and operators by preventing the machine from running under specific conditions for realizing the safety of equipment and human as well. Not only does it fulfill safety but also it is for performing the designed sequence of operation. If there is a problem, then it should be the solution for it. the solution is what so-called “Interlock”. So, what is interlock? And why do we need it? And how we can design a good interlock? Well! We may find such concerns exist in two aspects which are safety and operation sequence. In the f ...
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 ...
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, 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 doing great. In today's tutorial, we are going to design logic gates in PLC Simulator. It's our 4th tutorial in Ladder Logic Programming Series. We come today to elaborate the logic gates with comprehensive details for their importance in PLC programming. you can consider logic gates as the building blocks of ladder logic programming. Like every time we start with telling what you guys are going to have after completing this session? For those who like to buy their time and calculate for feasibility, I’d like to say by completing this article, you are going to know everything about what types of logic gates, how they are designed and how they work, how you can translate the logic in your head into the logic gate a ...
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 ...