Search WeChat Technical Training Imagine a DC power supply with three pins on its output socket: positive, negative, and ground. Correspondingly, the load’s plug should also have three pins that correspond to the power supply, allowing it to receive the energy supply correctly. Note that there are three essential conditions: The first is that the … Read more
The TIA V13 SP1 software provides two versions of Modbus RTU commands: Figure 1. Two Versions of Modbus RTU Commands The earlier version of the Modbus RTU command (MODBUS (V2.2) in Figure 1) can only communicate via the CM1241 communication module or the CB1241 communication board. The new version of the Modbus RTU command (MODBUS(RTU) … Read more
PLC Communication Protocol In modern industrial control systems, PLC is widely used. Programs can be easily modified and managed, thereby improving production efficiency, saving time and costs. The communication protocol of PLC is the communication support protocol for connecting different operating systems and hardware architectures. In simple terms, PLC usually controls the underlying layer, collects … Read more
Understanding the Modbus Protocol with PowerPoint Source: This article is reprinted from the internet, and the copyright belongs to the original author. If there are any copyright issues, please contact us to delete it promptly. Thank you! Scan to Follow WeChat ID｜13615417996 Follow the QR code on the left to get it for free [Siemens … Read more
Search on WeChat Technical Training When it comes to inverter communication, there are analog control, communication control, and terminal control. This article will guide you through the understanding of Modbus-RTU communication between the S7-1200 PLC and the HD20 inverter. Speaking of the Modbus-RTU communication protocol, I believe everyone is familiar with it, as it is … Read more
Click the “Technical Training” above and select “Pin to Public Account” Over 150,000 industrial control professionals follow this WeChat platform: technical sharing, learning exchanges, industrial control videos The day before yesterday, I discovered a true fan who comments every day on the articles shared by Technical Training. He suggested that I share some content on … Read more
Search on WeChat Technical Training 01 Siemens S7-200 SMART as Modbus Slave 1.Check the Micro/WIN SMART Modbus RTU Slave instruction library (Figure 1), which should include the MBUS_INIT and MBUS_SLAVE subprograms. 2.Use SM0.1 to call the MBUS_INIT subprogram for initialization, and use SM0.0 to call MBUS_SLAVE, specifying the corresponding parameters. Detailed explanations of the parameters … Read more
RS485 and MODBUS communication are commonly used concepts in industrial control systems, but they are different. Below is a brief introduction. RS485 is a physical interface, simply put, it is hardware. MODBUS is an internationally standardized communication protocol used for device data exchange between different manufacturers (generally for industrial purposes); in industrial environments, data is … Read more
The Modbus RTU communication protocol uses a master-slave response method for data communication. Requests can only be initiated by the master (PC, HMI, etc.) through a unique slave address, and the slave (terminal device) responds to the master’s requests, thus enabling half-duplex communication. This protocol only allows the master to initiate requests, and the slave … Read more
1. Introduction The HMI (Human-Machine Interface) is increasingly used in industrial automation systems and devices due to its small size, high performance, and strong real-time capabilities. It features various displays such as letters, Chinese characters, graphics, and images, with a simple and user-friendly interface. Equipped with long-lasting membrane button keyboards, it is easy to operate. … Read more