OpcPlcManager

OPC UA Method Example

Table of contents

• OPC UA Method Example
  • Table of contents
  • Introduction
  • Guide details
  • Quick-start example

Introduction

This example shows how to use OPC UA methods to execute functions in an ACF component written in C++.

To understand how to create and use OPC UA methods with PLCnext Control devices, the following tutorial should be completed:

https://github.com/PLCnext/OpcUaMethods

The concepts and procedures demonstrated in that tutorial were used to prepare this example.

This example also uses the PLC Manager RSC service.

Guide details

Description	Value
Created	19.03.2021
Last modified	05.06.2025
Controller	AXC F 2152
FW	2025.0
SDK	2025.0
PLCnext Technology Toolchain	2025.0

Quick-start example

It is assumed that the user has some experience building C++ Components and Programs for PLCnext Control.

Prerequisites:

• AXC F 2152 controller.

• PLCnext Technology Command Line Interface (CLI) tool, version 2025.0.

• A Software Development Kit (SDK) for the AXC F 2152 PLCnext Control, version 2025.0.

• PLCnext Engineer software.

• (optional) Eclipse IDE, with the PLCnext Technology feature installed.

• (optional) Visual Studio, with the PLCnext Technology add-in installed.

• UaExpert from Unified Automation.

Procedure:

• In PLCnext Engineer, create a new project based on the template for your PLC and firmware version.

• Change the OPC UA server settings so that "Visibility of variables" is set to either "Marked" or "All".

• Write and start the PLCnext Engineer project on the PLC. The only purpose of this PLCnext Engineer project is to configure the OPC UA server to make the GDS port variables, defined in our ACF component, available to OPC UA clients.

• Clone this repository, e.g.

  git clone https://github.com/PLCnext/CppExamples.git

• Copy the OPC UA Node Set file to the PLC (replacing the IP address with the IP address of your PLC), e.g:

  cd CppExamples/Examples/OpcPlcManager
  scp PlcManager.xml admin@192.168.1.10:~/projects/Default/Services/OpcUA/NodeSets

  This .xml file, in OPC UA Node Set format, defines the OPC UA methods that are implemented by our ACF component.

• Create a new ACF project using either the PLCnext Technology CLI tool, or Eclipse, or Visual Studio, with the following settings:

  • Project name: OpcPlcManager
  • Component name: OpcPlcManagerComponent
  • Project namespace: OpcPlcManager

• Copy the contents of the Examples/OpcPlcManager/src directory in this repository, to the src directory of the ACF project. Replace the existing source files with the same name.

• Build the ACF project.

• Deploy the ACF project to the PLC, using the .acf.config file in the Examples/OpcPlcManager/src directory. This configuration file includes the name of the component instance that is referenced by the Node Set configuration file.

• Restart the PLCnext Runtime.

• Start UA Expert.

• Connect to the OPC UA server on the PLC.

• Call the methods in the "PlcManager" node to read the current PLC state, and to stop and start the PLC component of the PLCnext Runtime.