For more exciting content, click to follow “PLC Enthusiasts” The Siemens S7-1200 can communicate via Modbus RTU through communication modules, with the PLC serving as the controller, typically acting as the Modbus master. When functioning as a Modbus master, it generally polls parameters from multiple slave devices. This article introduces the timed polling program for … Read more
Click đ above to follow Engineer Yan Ji and â starâ . Protocol Definition 1. Modbus is a request-response protocol implemented using a master-slave relationship. 2. The Modbus protocol introduces different application data units to change the packet format used in serial communication or to allow the use of TCP/IP and User Datagram Protocol (UDP) networks. Its … Read more
Click on the top “Technical Training” to select “Pinned Public Account” Over 110,000 industrial control professionals follow this WeChat platform: Technical sharing, learning exchange, industrial control videos Recently, many students have been asking about the MODBUS communication of the S7-200 series PLC, so today I will write an article to discuss how to use the … Read more
1. Design Philosophy of Modbus Protocol Modbus devices communicate using a master-slave (client-server) architecture, where only one device (the master/client) can initiate transactions (referred to as queries). Other devices (slave/server) respond by providing requested data or performing operations as requested in the query. Slaves are any peripheral devices (I/O converters, valves, network drives, or other … Read more
In order to achieve information collection and command output over as large a range as possible, we need to distribute the IO through a fieldbus. How can this be achieved? The answer is to connect several IO couplers on the communication bus, which communicate data with controllers such as PLC. The PLC and other controllers … Read more
These communication standards play different roles in industrial automation. Let me use a traffic system analogy to help you understand: Basic Positioning of the Four Standards 1. RS-232: A One-to-One Small Road Features: The earliest serial communication standard (1969) Point-to-point full-duplex communication (simultaneous two-way) Single-ended signal transmission (susceptible to interference) Typical transmission distance ⤠15 … Read more
In modern industrial control, we often encounter situations where Modbus IO needs to connect to CANopen IO. How can we achieve interoperability between these two different communication protocols? PXB-6021 is a newly launched Modbus to CANopen protocol converter from Zhiyuan Electronics. It features 1 CAN channel, 1 100Mbps Ethernet port, and 1 RS485 port.This product … Read more
Hello everyone, I am Da Yi, and today we are going to talk about the serial communication protocol between microcontrollers (MCU) and PLCs. When it comes to serial communication, many of you might feel confused, but donât worry, I will clarify everything shortly. What is Serial Communication?Communication is everywhere; for example, the way you and … Read more
I remember when I first joined the industry, I took over a project to upgrade an injection molding machine. The communication between the inverter and the PLC was always intermittent. After several days of troubleshooting, I discovered that the grounding was not done correctly, which caused interference. Today, I will share my experiences and techniques … Read more
ClickFollowâPLC Wireless Communicationâ for daily amazing discoveries! Is RS-232 a standard communication interface or a protocol?? Is RS-232 a bus?? What is the relationship between fieldbus and networks?? Does each bus have a protocol?? What is the main function of the PLC communication module?? It’s all a mess, please advise, thank you. Whoever can explain … Read more