I remember once visiting a food factory where the owner spent over twenty thousand on a packaging machine. Suddenly, it stopped working! When I opened the electrical cabinet, the indicator lights on the Siemens S7-200 SMART were flashing like it was New Year’s. The operator was as anxious as a cat on a hot tin … Read more
Connecting a PLC to an energy meter? It sounds quite sophisticated, but it’s similar to connecting a Bluetooth headset to a phone; it’s just two devices communicating with each other. Modbus is the “language” they use to chat, which simply means sending and receiving data in a specific format. The S7-200 SMART is a compact … Read more
Introduction: The “Telephone System” of Industrial Energy Meters Imagine hundreds of energy meters in a factory like silent soldiers, and you have no way of knowing their real-time data—this information black hole is something every engineer has experienced. Today, we will reveal in simple terms how to build an “industrial telephone system” using the S7-200 … Read more
Supported baud rate range: 9600—-12M Order number: 6ES7-277-0AA22-0XA0 1. First, install the GSD file for EM277 (GSD file download link: http://www.con-star.com/download/download11.html) 2. In the path PROFIBUS DP—Additional Field Devices—PLC—SIMATIC—EM277, drag it into the DP line configuration 3. Click on “EM277 profibus dp” to see various types of communication data classifications, such as “2 BYTE OUT/ … Read more
First, we will introduce our hardware preparations. 1. A weighing instrument that supports the Modbus protocol Weighing instrument that supports the Modbus protocol 2. Set the communication parameters of the instrument You can adjust according to your requirements, as long as it matches the PLC side. Baud rate: 9600 Data format: 8n1: 8 data bits … Read more
How to determineif a Modbus TCPconnection is established? Answer: To performModbus TCPcommunication, a connection must be established. S7-200 SMART CPUas aModbus TCPclient: You can determine the connection status using the Modbus TCP Client instruction’s symbol table parameter mConnected, as shown in Figure 1. If mConnected=1, it indicates that the connection has been established, while mConnected=0 … Read more