TILI Automation

 In this article, we will learn about a watchdog timer in the Siemens PLC. As we know that in the PLC when CPU process the logic it takes a certain amount of the time. The amount of time the CPU takes to process the logic depends on the size of the program. So, scanning from the first network to the end of the program is called one scan cycle. For one scan cycle, time must not exceed defined cycle time and amount of time it takes to process the logic. Watchdog Timer in PLC To check a cycle time open TIA portal. In the programming environment go to the main CPU. Do a right-click and click on online and diagnostics. The following new window will open up. Choose the cycle time option from it. One thing to note is that to see cycle time you must have to stay in the online mode. In the offline mode, you won’t see anything. In the above window, you can see a cycle time. In the cycle time measured tab, you can see a cycle time of the current program. In the cycle time set option, the maxi...

 In this article, we will learn about the information you can get from the resources tab of the Siemens PLC. Resources as the name indicate it contains all the information related to the PLC program. Let’s take a software tour and find out where the resources tab is and what it contains. Here, I will show you in the both TIA PORTAL and the Simatic manager. Resources Tab in Siemens PLC Let’s first open TIA PORTAL. Enter into the programming environment. On the left side select the CPU and do right-click on it. From the list choose “call structure”. The following window will appear. On the right side in the corner, you can see the “resources” tab. Click on it. As you can see in the below window in the resources tab you can have detailed information of the used and unused I/Os, CPU memory, and memory space consumed by programming and data blocks. In the CPU memory, you can see the amount of the used and remaining memory. The same way you can access all the information about the progra...

 In this article, you will learn about the CP (Communication processor) module used in the Siemens PLC. CP module is used to transfer the data in a case of not having the required port on your CPU. Communication Processor Module For example, we have a redundant system installed in a plant. We have an S7-300 series of CPU 315-2DP is installed. On the first rack, we have power supply and CPU is installed, the same way for redundancy one more CPU with power supply is installed. On the second rack, two IMs are installed as you can see in the below window. Now, both CPUs are communicating with IMs through the PROFIBUS-DP network. But how the 1st CPU will exchange the data with the 2nd one? First, you may think of the second MP (Multi-Point Interface) to exchange the data. But as you know MPI is a very slow network and it is not possible to send out a large amount of the data using this network. If you use MPI to exchange the data then you only have to use the MPI network throughout the ...

 In this article, you will learn about PID instruction with the help of a practical example. Here, I will consider a practical application to control a manipulate variable to maintain a set point of the process. PID means proportional, integral and the derivative is a controller used to control the processes by adjusting the manipulated variable to keep process variable at a set-point. Nowadays it is easier to work with PID as it comes inbuilt in PLC programming software with a lot of features. Here, I will consider an example of one process. To maintain the process variable at a set-point I will write a PLC program. PID with Practical Example Let’s consider a temperature control loop in which I have to control the temperature. Here, consider a range of the transmitter from 0 to 300 °C. I have one control valve in line to control the temperature. So at 0% opening of the valve, the temperature will remain the same process temperature as it is. Now let’s say the temperature is 100 °C...

 In this article, I will cover how to work with an emulator in the Rslogix 500 of Allen-Bradley PLC. Many people face an issue while working with Rslogix500 and its emulator. Always note that if you want to work with an emulator or want to write the PLC program you always have to open the software as an administrator. Allen Bradley RsLogix Emulator To work with Rslogix 500 you need three software. Rslogix 500 Rslinx for communication, Emulator to test the logic. Let’s see how we can test the logic using the emulator by following the below steps. Step 1: Open Rslogix500, rslinx and Rslogix 500 emulator as an administrator. First, go to Rslogix500 and create a new project. Enter in the programming environment. Step 2: Write the program to test the PLC logic. Here, I will write a program to energize an output for ten seconds and other output to energize after 10 seconds. Step 3: To test the logic, go to Rslinx. Click on an icon as shown in the red square. Step 4: The following window ...

 In this article, I will explain to you about the use of the JUMP instruction using Siemens TIA PORTAL The jump instruction is used to skip part of the logic or rungs during the program run. Now, why JUMP instruction? You may ask. The simple answer is to reduce scan time (one of the advantages). To jump unnecessary logic which we don’t want to execute while program in run mode can reduce the amount of scan time. Also Read: JUMP Example Let’s dig deeper to understand JUMP instruction with the help of an example. Jump Instruction in Siemens Tia Portal Open TIA PORTAL. Enter into a programming environment. I have added little program in the second network as you can see in the below window. Now, I want to skip that second network. To do that I have added JUMP instruction in the first network. In the third network, I added a label, which indicates the location of the jump. To use JUMP instruction, you have to define it. You can define any name but always remember to use the same name a...

 This article is about the function of the masking in the PLC. Here, I will use Siemens TIA PORTAL. Masking helps us to cover something or mask which you don’t want to see. In the PLC terms Masking means to filter the data which you don’t want to use while execution of the PLC programming. You may have noticed when you make a purchase, At the time of payment when you enter your ATM card number, it won’t allow you to use any alphabet that what you can call is masking. Masking in PLC Let’s understand the function of masking with an example. Do follow the below example and also play around with the different values to understand it. For example, let say I have a temperature transmitter. As this is an analog signal data type, so we need a word or doubleword data type. I want that if PLC receives a signal from a temperature transmitter, I need some data to masked off. The bit which I want to mask off is “00FF” which in binary represented as “0000 0000 1111 1111”. Now we will implement t...