Schneider PLCs use several communication protocols to connect and control industrial devices efficiently. The most common protocol is Modbus, originally developed by Modicon, now part of Schneider Electric. Modbus comes in two versions: Modbus RTU for serial communication over RS-232 or RS-485, and Modbus TCP/IP for Ethernet-based connections. These protocols allow Schneider PLCs to exchange data with other controllers, sensors, and computers reliably. Besides Modbus, Schneider PLCs support EtherNet/IP, an Ethernet-based protocol following the Common Industrial Protocol (CIP) standard, which is widely used in modern automation systems.
Some Schneider PLCs also support MQTT, a lightweight publish-subscribe protocol suitable for IIoT applications, enabling machine-to-machine communication. Schneider’s proprietary UMAS protocol is used for configuring, monitoring, and controlling their controllers, often running over Modbus/TCP. Depending on the PLC model, fieldbus protocols like CANopen, AS-i, and PROFIBUS are also supported. Additionally, many devices allow serial communication, wireless connectivity, and network management via SNMP. Using these protocols, Schneider PLCs can handle diverse industrial automation tasks, integrate with modern IIoT systems, and maintain reliable communication across various devices and networks, making them flexible and future-ready for complex industrial environments.