Die durch die klassische Namur-Pyramide beschriebene Automatisierungsstruktur ist bewährt und ermöglicht langjährige Betriebssicherheit. Allerdings fehlt den Systemen die Offenheit, neue Technologien werden erst spät verwendet und die Kosten sind hoch, was angesichts der rasanten Entwicklungen im Bereich von Internet of Things, Industrie 4.0, Mobile Devices und Big Data nutzvolle Innovationen verhindert. In diesem Beitrag wird das im Namur-Arbeitskreis 2.8 Automatisierungsnetzwerke und -dienste entwickelte Konzept Namur Open Architecture (NOA) vorgestellt. Das Konzept bietet sowohl für Bestands- als auch für Neuanlagen Möglichkeiten, um Anlagen effizient für kommende Innovationen zu ertüchtigen. Die Kernidee ist, die Daten der bisherigen Kern-Automatisierungswelt durch offene Schnittstellen wie beispielsweise OPC UA in die Systemwelt für Monitoring- und Optimierungsaufgaben zu exportieren und dabei die Kernautomatisierung weitgehend unverändert zu belassen. Alternativ kann über einen zweiten Kommunikationskanal direkt auf die bestehenden Feldgeräte zugegriffen werden.

Devices in industrial automation systems are becoming more and more intelligent. Consequently, functions such as server services are migrating into the device level. To solve the resulting connection mesh, this paper entails the concept of aggregation of servers connected to devices in an industrial automation scenario. The first section discusses the basic requirements for aggregation and proposes an architecture for server aggregation as a solution. The following section describes the building blocks of the architecture. Finally, the paper presents a prototype based on this architecture model as a proof of concept implementation of the concept introduced in this paper. The last section discusses the results of the prototyping phase including the possible improvements of the same.

In industrial production scenarios, there is often a need to access heterogeneous information sources such as production units but also DBMS (Data base management system) and/or a local or shared file system to realize the necessary workflows. EDDL (Electronic Device Description Language) provides a standardized way to access and exchange information with the devices that make up the automation system. This paper discusses an approach to use the EDDL approach to describe databases and files, which is to say that in this approach the databases and files both have been modelled as 'devices' and can be communicated with like any other device with its own device description. For this to work, EDDL based device descriptions were formulated for databases as well as files and the communication with the same was established with the help of an OPC UA Server, containing nodes corresponding to database entries and files (of a local file system), in its address space. The OPC UA Server used the EDDL based descriptions of the file system and databases to gain connection and access related information about the same, thus establishing the communication. The results of this approach have also been discussed in the following sections, along with a proposal for some enhancements to the EDDL standard. Observations and Future WorkAn important observation that came through during the development of this concept is the communication model for EDDL. Due to the fact that the communication standards targeted by EDDL such as Profibus and HART currently operate on a request response model, EDDL also follows this model. Therefore, for each access the EDD file needs to be consulted to find out the correct communication command for the request, which needs to be issued in order to retrieve the information from a device. However, other communication protocols natively provide subscription mechanisms and events that are not supported by EDDL. For example when we would like to subscribe to the value of a particular variable, we expect to receive periodic updates about the value of that variable, or whenever the value changes. In an event based communication model events are generated based on some specific preconditions. To overcome these limitations, we developed and implemented an extension to the EDDL model with possibilities for the inclusion of communication protocols that provide subscription and event based communication in the existing communication definition of EDDL. In our model we have defined commands (in the EDD file) for subscription to nodes in the address space, which is essentially and even based service. When a client subscribes to a particular node, the EDD file provides information about how to subscribe to the underlying entity, the ServerEngine (described above) takes care of the event management and generates OPC UA subscription events whenever the value of the underlying entity changes. The way subscriptions are handled in the underlying devices might be different in this case which is managed by the communication driv...

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Das Konzept Namur Open Architecture (NOA) wurde auf der Namur-Hauptsitzung 2016 vorgestellt, im Jahr 2017 gab es erste Demonstratoren. Inzwischen werden drei konkrete Elemente des NOA-Konzeptes erarbeitet: Die NOA-Diode sorgt für den sicheren Datenexport aus der Namur-Pyramide, das NOA-Informationsmodell beschreibt die Daten und Bezeichnungen, und Verification of Request erlaubt einenkontrollierten Datenfluss zurück in das Prozessleitsystem der Anlage. Diese Elemente wurden an der IGR-Testanlage im Industriepark Höchst implementiert. Im Beitrag werden vier konkrete Anwendungsfälle für die NOA-Bausteine vorgestellt: eine Pumpendiagnose, die automatische Aktualisierung der Dokumentation nach einem Sensortausch, die Online-Überwachung eines Prozessanalysegerätes sowie ein Dimensionierungs-Check für Feldgeräte.