TILI Automation

 In this article, we will learn about the execution of the program in the PLC. Many people want to learn PLC programming directly without knowing what happens around it. Before jumping into the programming, you must learn the basics of the PLC, how the program works, the flow of the program, and during execution how it uses memory, etc. How CPU Execute Program in Siemens PLC? Here we are going to learn about how CPU executes a program in the Siemens PLC, although execution will remain the same in every PLC, in Siemens PLC it will take a little extra for an execution. Normally in every PLC execution takes place like reading the Input, evaluate the logic and writing the output, However, in the Siemens PLC, it reads the inputs from the input module then values are saved to PII (Process Image Input). PII is a small memory part that resides in the CPU to store the status of the inputs coming from the input module. Now you may have a question that why to save the value to PII? It’s becau...

 In the previous article, we learned how to save a project to a memory card. Now in this article, we will learn how to retrieve the PLC project which we have saved to micro memory card (MMC). Retrieve PLC Project From Memory Card After saving the project to memory card (MMC), if in case you lost your PLC program then you can retrieve your project by following the below steps. Step 1: Open Simatic manager. Step 2: Close the Simatic manager window and click on an icon as shown in the below window. Step 3: The following window will pop up. Chose your project and go to “PLC” and choose “retrieve from memory card”’ Step 4: Select a project and hit “ok” to proceed. Step 5: A progress bar will pop up to indicate that transfer of the project from MMC is running. Step 6: The following pop up will open. Hit “ok” to proceed. Step 7: A project is retrieved now. END

 In this article, we will learn about a method to delete a CPU memory in the PLC. When you use a selector switch on the CPU of the PLC you must know what it reset within a memory. When you reset or delete a memory, it only deletes a memory variable values and not whole memory. Delete Siemens CPU Memory To reset the memory first put your CPU into the STOP mode. Now, move your selector switch to “MRES” mode and keep it till the STOP LED starts to blink. As LED stops to blink, put your CPU into the STOP mode again. You have successfully reset the memory. But as you know that it only deletes memory variable values and not whole memory. To delete the whole memory, do follow the below steps. Step 1: Open TIA PORTAL or Simatic Manager. Open Block section. Step 2: To delete it hit ctrl + A on your keyboard. Uncheck system data. Click on “delete”. Step 3: Hit “yes” to delete. Step 4: The whole memory is deleted now which you can confirm by looking at the block window.

 In this article, we will learn about peripheral inputs and outputs in the Siemens PLC. In my previous article, I covered the execution of the PLC program and gives an idea of PII and PIQ, which are small storage section in the CPU. For digital input and output, logic action is stored to PII and PIQ to fasten cycle time. But, for analog input and output, it directly takes value from the card itself. To recognize addresses of analog input and output, say PLC that not look at PII and PIQ instead, it will look at analog card directly so we need to use a peripheral address. Peripheral Inputs and Outputs Before writing any analog address to the programming you must have to add “P” before any analog address you choose. For Simatic manager software above mentioned addressing method is used to recognize analog signals. For example, PIW100, PID100, PIQ200, etc. For TIA PORTAL it accepts “P” after and before the address. For example, PIW100 or you can write IW100:P Let take an example in bot...

 There are times in which we want to acquire all our PLC’s data into a spreadsheet to get a clear view or something. Now let’s see How we can communicate with Microsoft Excel from RsLinx to write the data to excel? I am using RsLogix 500 here to communicate with Rslinx. You can also use RsLogix 5000 also. Now I will create a sample program in Rslogix 500 to communicate with Excel. I have created a Reset timer for 20 seconds. Basically, the timer runs for 20 seconds and resets itself and runs again endlessly. The communication protocol we are gonna use here is the Dynamic Data Exchange or DDE protocol. Training: Allen Bradley PLC Communicate with Excel Now let’s got to Rslinx, First of all, create a communication driver Emu-500 for running the program in an emulator. Now go to DDE/OPC then click on the topic configuration. A dialog box opens up as shown below. The driver we created will be shown on the right side of the box Click on the Plc icon that is shown. The Model of the proce...

 In this article, we will learn about a term test and process mode reside in the TIA PORTAL software. These two options you may find in some PLC and not in every PLC. It depends on the type of PLC you choose. Test and Process Modes Let’s find out where these functions are residing in the PLC software. Open TIA PORTAL. Go to “Device and Network”. Now, select the CPU and go to the “properties tab”. This is a safety CPU which contains operating mode. Here, in the “general” tab section you can find “operating mode” as you can see in the below window. Inside operating mode, you can find two options 1. Process mode 2. Test mode Selection by default comes in test mode. Test Mode: As you can see in the above window that selection is at by default test mode. In test mode you can perform test functions means you can modify and monitor variables. In the test function, you can perform every function without any restrictions. But it requires greater scan time. So, if a user program is in test m...

 In this article, I will discuss the types of Allen Bradley PLC used from smaller applications to a higher one. While designing a control system it is important to know about the PLC type you require. Larger the project is, the higher end PLC requires to fulfill needs. There are many three types of PLC you can use, MicroLogix CompactLogix ControlLogix These three types of PLC have their capability of handling the process. They are greatly differentiated by their software, expansion module limitation, memory space, and communication protocol. MicroLogix This type of PLC is used for the small control system. We can use where less I/O’s is required. Cost-effective solution for small scale applications. Use rslogix500 software for the programming. It comes with fixed I/Os (onboard I/O). No physical rack is required.as input and output cards are connected using a ribbon cable. The supported communication port is RS-232/485, an Ethernet port. The controller supports 32 discrete I/O point...

 LIFO is a special programming instruction that can be used in the applications that require to store the sequence of data in order and unload it. Now we are gonna see how are loading and unloading done in LIFO. LIFO Instruction in PLC Yes! LIFO should be used in a pair. There should be an instruction to load and there should be an instruction to unload. The following are the block parameters in LIFO load instruction, Source: Here is where one should give an address where the values to be loaded are present. LIFO: Here is where one should specify the address where the values have to be loaded. This address seems weird right with an ‘#’ in the front. When we use an ‘#’ symbol in the front, It is called an array of addresses. Obviously there will be a sequence of values present to be loaded arrays are capable of storing many values right? So why we gave ‘#’ in the front should make sense now. Control: Here is where one should specify the control address. In the Rockwell PLC programmi...

 The Protocol is nothing but a communication bridge. A communication bridge established between two software devices, or even between two persons can be called a protocol. DDE was first introduced by Microsoft back in 1987. So coming on to DDE protocol, DDE stands for Dynamic Data Exchange. As the name indicates, the data can be transmitted from time to time. That means the data can be transmitted or read on a real-time basis since it is a dynamic data exchange. Dynamic Data Exchange (DDE) Dynamic Data Exchange (DDE) is an interprocess communication system that allows data to be communicated or shared between the applications in operating systems such as Windows. Dynamic Data Exchange works based on client and server model communications. The client is the application that is requesting the data and the one that is providing the data is called server. DDE doesn’t use any specific functions or libraries. Which makes it easy for anyone to use this protocol. DDE can be used to impleme...

 In this article, we will learn about the interface module (IM) used in the Siemens PLC. The data transfer between I/O modules or between higher levels of PLCs takes place via an interface module. I know that many people have heard this word remote I/O, this is achieved by installing an interface module. Remote I/O is used to reduce long wire run, reduce complexity while troubleshooting, and provide a cost-effective solution. Let’s assume that in the plant we have to install a bunch of field devices that are far away from the control room. In such a case instead of pulling wires from field to control room can increase the cost significantly and also make troubleshooting of a system more difficult. To make things simple, first, move all the I/O modules to the field area and add interface module with it. Now, connect supported communication port from the control room’s CPU to interface module to establish communication with each other. This way you only require one cable for communic...

 To Understand Trends, we need to understand how crucial role is the data we're collecting from the field Instruments plays in an automation system. Let’s say we are acquiring data from a group of sensors in an automation plant. We can either display it as in values digitally or we can display it in a Graphical chart. Graphical Chart is one of the most convenient methods to view a group of data for anyone to identify the changes taking place instantly by looking at the waveforms. Trends In SCADA graphical display of Data is called Trends. There are two types of Trends, Real-time trends Historic trends Real-time Trends As the name explains itself, these are the graphs that display the values of data in real-time and the graph updates for every instant of time we have specified. Now let’s see how to implement in in Intouch SCADA, I am using Rslogix500 here and reading data from PLC and displaying it in a graph, For the communication between Intouch and Rslogix500 refer to the article...

 What is Recipe Management? and How can it be implemented on Intouch? So to get started we will see what I am referring to a recipe. There are many batch processes in the industries. For Example, let’s say the industry is manufacturing a Tea powder, coffee powder, and, Milk powder. They have a set of materials in Silo or containers and each product requires a different amount of each material that is to be mixed together in a mixer. Now, Imagine there are 5 Silos or Containers where the raw materials are stored. For each Recipe or a product the operator selects, the required ratio of the raw materials will get assigned and a trolley or container will collect the specified amount from each silo. So we have to define the recipe and store it as a CSV file. So when an operator presses a button the data on the CSV file will get assigned to the tags. Recipe in SCADA Now let’s see how to assign Recipe in Intouch SCADA, After opening a new project on Intouch, got to Applications – Recipe m...