Hi friends and hope you are doing very well. Today we would like to take one tutorial which is very essential in the industry which is analog input processing for handling analog measurements of physical signals like temperature, humidity, pressure, distance, flow and level of liquids, etc. Typically, sensors produce two types of analog signals to represent the equivalent measured signal which is current and voltage signals. The currently produced signals would be within the range of 4-20 mAwhile voltage signals are in the range of 0-10 v. because, that output signals represent physical signals, the limits of output signals are 0 to 10 v for voltage based sensors and 4 to 20 mA for current-based sensors, these values should be scaled to represent ...
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 ...
Hi friends, today we are going to learn one of the most important instructions in the PLC ladder which is MOVE instruction by which we can move data between different memory storage including input, output, marker, and variables. Also, data of different data types and sizes can be transferred from source to destination and source memory locations. For example data types including char, string, integer, floating, time and date can be transferred between source and destination. Memory location like input, output, and marker memory area can be acting as source or destination. Furthermore, a mask can be utilized to customize and control the part of data to be transferred between source and destination. In that move with a mask, the instruction uses a source address, a destination address, and ...
Hi friends, today we are going to learn a good technique to run multi outputs in sequence. In another word, when we have some output that is repeatedly run in sequence. In the normal or conventional technique of programming we deal with them individually or one by one which takes more effort in programming and much space of memory. So instead we can use a new technique to trigger these outputs in sequence using one instruction which will save the effort of programming and space of memory. In this article, we are going to introduce how to implement sequencer output instruction. And practice some examples with the simulator as usual. Before starting the article, we need to mention that, some controllers like Allen Bradley have sequencer output instruction and some has not like Siemens. So we ...
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 ...
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 Guys! hope you are doing great today! We come this time with a complete project to work out together starting from the point at which we sit with the client and receive the logical narratives that represent what they want to implement. We are going to start with a simple project this time and continue increasing the scale and complexity of the requirements through the incoming tutorials. The project we are going to implement today is one of the most common tasks that we can find in every place in our real life which is the control of the garage door. That could be found in private property or commercial buildings or public garages. Too many things need to be controlled in garage doors and several scenarios could come to your mind. However, take it as a rule of thumb that we design our p ...
Hi friends! I hope you are doing well! Today we are going to learn and practice a new topic which is a very crucial technique in plc programming. the topic is called “latching”. We mean by Latching to keep the output running starting from the instance of giving a kick-off command until we hit a command to stop running of the motor. Imagine my friends, operator wants to start a motor by hitting a start push button and want the motor to keep running and leave and go for doing another task or job. And then it keeps running until the operator wants to stop it. The problem here is that, once the operator releases his hand away from the push button, the motor automatically stopped and that is not like what the operator wants to do with the motor. To clear the problem that we are going to solve, ...
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 ...
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 ...
