OPC Unified Architecture

What is OPC UA?

OPC UA is an open communication standard for exchanging data in industrial settings. This article will give you a detailed and beginner-friendly introduction to the basics of OPC UA. In addition to the functionality and the most important features of the OPC UA standard, we will discuss information modeling and specifications as well as the importance of OPC UA for the industry.

Definition

What is OPC UA?

OPC UA stands for OPC Unified Architecture and is an open communication standard for industrial data exchange.

With the help of OPC UA, complex data from industrial controllers and other sources can be provided in a standardized format and retrieved and processed by a wide variety of applications. OPC UA also provides an interface for managing and automating processes.

OPC UA is based on a client-server model:

  • An OPC UA server provides data from one or more sources (e.g. industrial controllers).
  • IT applications such as MES (Manufacturing Execution System), ERP systems (Enterprise Resource Planning) or cloud platforms use OPC UA client software to retrieve the required data from the OPC UA server, transmit data themselves or interact with the source in other ways.

Many modern industrial devices and machines implement their own OPC UA servers and therefore offer native support for OPC UA. However, data from older systems can also be provided and processed in OPC UA format using an external OPC UA server.

OPC UA was published in 2008 and is a successor to the classic OPC standard. You can find out more about the significance of OPC and OPC UA in the last section of this article.

Characteristics

Characteristics of OPC UA

OPC UA was developed by the OPC Foundation to meet industry-specific requirements for data exchange between a wide variety of systems. As a result, the OPC UA communication standard is characterized by some core characteristics:

Platform independence:
In contrast to the classic OPC standard, OPC UA is no longer dependent on the Windows operating system. Previously, OPC servers and OPC clients had to be installed on Windows computers and communication between server and client was only possible via Microsoft’s COM/DCOM model. With OPC UA, data exchange takes place via the common Internet protocols TCP and HTTPS. This means that OPC UA software can be installed on any system that supports Internet communication.

Flexibility and scalability:
OPC UA enables standardized communication with a wide range of industrial systems – from the smallest devices to large distributed systems. New systems can therefore be integrated into an OPC UA-based infrastructure quickly and with comparatively few adjustments. This not only reduces the IT effort for individual solutions, but also offers greater scope for innovation by eliminating compatibility problems.

Complex information modeling:
In contrast to the classic OPC standard, where individual variables are provided as tags, OPC UA supports comprehensive information modeling. This is based on so-called “nodes” and relies on concepts from object-oriented programming. Real objects and their status can be represented digitally. Methods can also be defined that can be called up by OPC UA clients in order to interact with devices and machines in a targeted manner.

Future-proofing:
The OPC UA standard is being continuously developed by the OPC Foundation in order to meet the changing requirements of industry. An important requirement here is compatibility with current and future technologies in order to ensure that investments in industrial automation technologies are future-proof. Many definitions in areas such as data modeling and data transport have therefore been deliberately kept abstract to enable seamless integration of new technologies and innovations.

Security:
The OPC UA standard defines various mechanisms to ensure security in industrial data exchange. In addition to HTTPS encryption during data transport and user authentication, OPC UA supports the exchange of certificates between OPC UA clients and OPC UA servers.

Digital production management in the cloud

With the cloud platform manubes, you are able to systematically automate production processes and visualize all areas of a production in real time.

manubes supports OPC UA to communicate securely & easily with all kinds of machines, devices and other systems.

The manubes platform offers worldwide access via web browser, easy operation and maximum security for production data.