OPC UA session Creation The eUA server supports a limited amount of concurrent sessions depending on the controller type (Device-specific OPC UA settings). The server verifies the ClientCertificate for secure endpoints when creating a session. Make sure that the ApplicationURI specified in the ApplicationDescription matches the… Read More
Reverse Connect Available from firmware version 2022.9 What problem should be solved In some automation applications the PLCnext Control device is connected to the internet. In this case, a basic security requirement is to reduce the open ports to prevent attacks from the internet. The Reverse Connect… Read More
OPC UA client Available from 2023.0 LTS The OPC UA client supports subscribing variables from connected servers and writing changes of local variables to connected servers. The PLCnext Control device establishes the connection automatically as soon as the server is available. When the connection gets lost, the OPC UA… Read More
OPC UA client XML schema Schema file The connection configuration is defined in XML files. It is based on the standard UA schema for data types which can be found here. It is formally defined in this schemathis schema. … Read More
Global Data Space The GlobalDataSpace namespace All programs and variables from the IEC 61131 context are displayed in the http://phoenixcontact.com/OpcUA/PLCnext/GlobalDataSpace/ namespace. Via the namespace, the corresponding NamespaceIndex can be determined from the NamespaceArray. The NamespaceIndex is a numeric value for identification of the namespace. It is saved in the… Read More
Quickstart OPC UA server configuration Tutorial video Note: Tutorial videos are embedded from the Phoenix Contact Technical Support YouTube channel. With playing an embedded YouTube video in this platform, you accept the YouTube Terms & Conditions. Even showing the video previews on this page depends on your personal settings. To… Read More
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… Read More
Introduction to information models The PLCnext Technology eUA server provides these IEC 62541-5 compliant information models: External information models Alarms and conditions Device information Historical data access File access Global Data Space Common OPC UA terminology This topic describes some common OPC UA… Read More
OPC UA alarms and conditions Alarms You can exchange alarm and status messages between a program and the eUA server. For all details, please refer to the Alarms via OPC UA section. • Published/reviewed: 2026-07-10 ☀ Revision 098 • … Read More
eUA Client diagnostics Available from firmware version 2024.6 Overview Diagnostic information of the eUA Client is accessible via the eUA Server. The eUA Client object can be found in the server address space by the following path: Root → Objects → DeviceSet → Controller type (for… Read More
