Overview to OPC UA with PLCnext Technology
OPC Unified Architecture (UA) is a standardized protocol for industrial IT and OT communication. The following areas of OPC UA are integrated in PLCnext Technology and can be used in your application.
OPC UA Server
On request, an OPC UA server provides an OPC UA client with process data and variable values from a running application.
The PLCnext Control devices contain an embedded OPC UA server (eUA). In addition to the runtime, it is integrated in the controller. It enables access to components, programs, function blocks, structures and variables of PLCnext Technology.
OPC UA Client
The OPC UA client supports subscribing variables from connected servers and writing changes of local variables to connected servers. The PLCnext device establishes the connection automatically as soon as the server is available. When the connection gets lost, the OPC UA client tries to reestablish the connection continuously.
The OPC UA client is available for all PLCnext Control devices starting with firmware version 2023.0 LTS.
OPC UA PubSub
From firmware release 2022.0 LTS, PLCnext Technology implements the Server-independent, publish-and-subscribe mode of communication according to IEC 62541-14.