In the upgrade and transformation of old equipment projects, it is inevitable to involve the replacement and upgrade of PLCs. However, sometimes the original PLC program of the control system is lost, and a complete annotated original program cannot be found; at other times, the original program may contain proprietary technology blocks; or sometimes the … Read more
1. Core Communication Protocols: The Engineer’s Toolbox We categorize the most commonly used communication methods into three main types to facilitate quick selection in your projects. First Type: The most integrated and mainstream “one-stop” solution 1. PROFINET (Key Focus) This is the absolute mainstream and preferred choice for Siemens S7-1200/1500/400 series, representing the implementation of … Read more
The Role of Termination Resistors on Siemens PROFIBUS DP Connectors (Commonly Known as ‘DP Connectors’). Core Function Summary:The core function of termination resistors is to match the impedance at both ends of the communication bus to eliminate reflected wave interference caused by impedance discontinuities at the ends of the transmission line. In simple terms, it … Read more
There are many knowledge points to master regarding Siemens PROFIBUS-DP, and the difference between knowing and being familiar with them is quite significant. Previously, we received feedback from some users requesting more information on this topic. Therefore, today I will mainly share the three types of devices defined by Siemens PROFIBUS-DP. If you find this … Read more
In the vast realm of industrial control, Siemens stands out like a brilliant star. As one of the earliest industrial control manufacturers to enter the Chinese market, it maintains a formidable market share. Its PLC products attract the attention of many industrial control professionals with their exceptional quality, stable networks, and open compatibility, much like … Read more
1. Configuration in TIA Portal In TIA Portal, create a new project. This case selects the Siemens S7-300 PLC, model CPU 313C-2DP. This PLC is an integrated PLC with a built-in PROFIBUS-DP port, which can act as a master or a slave. In this case, the PLC acts as the master. Step 1: Add the … Read more
Practical Application of Profibus DP Data Acquisition You may have heard of Profibus DP (Decentralized Peripherals), a protocol frequently used for data transmission in Siemens PLC projects, especially in industrial automation, where it is widely applied. Today, let’s discuss how to use Profibus DP for data acquisition, allowing it to easily interface with PLCs to … Read more
1. Fatal Fault on Site A certain automotive welding workshop, Siemens S7-300 PLC (6ES7 315-2EH14-0AB0) suddenly reported error 0x1A3B, with 32 DP slaves going offline collectively. The monitoring screen displayed:<span>[2023-05-12 03:15] PROFIBUS-DP System Fault: Telegram timeout (Slave 17-32)</span> The signal amplitude was only 0.8Vpp (standard requirement ≥1.5Vpp), with a rise time jitter of 35ns (IEC61158 … Read more
To build a stable and reliable Profibus-DP network, termination resistors can be considered a “small component with a big role”! Many engineers often overlook their importance, resulting in spending several days troubleshooting inexplicable communication failures, only to find out that it was the termination resistors causing the trouble. Today, we will analyze this seemingly simple … Read more
In a Profibus-DP network, the bus length is one of the key factors affecting system stability. As the bus length increases, signal attenuation, delay, and interference also increase, which changes the requirements for termination resistors. Today, we will discuss in detail how to correctly choose and install termination resistors for different lengths of Profibus-DP buses. … Read more