Production facilities utilize various networks to virtually connect their machines. Industrial PLCs communicate over protocols such as EtherNet/IP, PROFINET, Modbus TCP and OPC UA, depending on the platform and the devices on the network. The protocol determines how the controller exchanges data with drives, sensors and plant systems. These PLC communication protocols are employed by different OEMs:
- EtherNet/IP: An industrial Ethernet protocol common on Allen-Bradley and Rockwell systems for device and controller messaging.
- PROFINET: The industrial Ethernet standard used across Siemens SIMATIC systems for operation data exchange.
- Modbus TCP: A widely supported open protocol used to connect mixed vendor devices on one network.
- OPC UA: A platform-independent standard that moves data securely from the controller to MES, SCADA and analytics systems.
Protocol choices matter most where controllers tie into larger SCADA and plant networks, like water and wastewater systems. See the industries Adgo serves for where this comes up.
