OPC Foundation

OPC is the interoperability standard for the secure and reliable exchange of data and information in the industrial automation space and in other industries. It is platform independent and ensures the seamless flow of information among devices from multiple vendors. The OPC Foundation is responsible for the development and maintenance of this standard.

OPC UA is a platform independent service-oriented architecture that integrates all the functionality of the individual OPC Classic specifications into one extensible framework. This multi-layered approach accomplishes the original design specification goals of:

  • Platform independence: from an embedded microcontroller to cloud-based infrastructure
  • Secure: encryption, authentication, authorization and auditing
  • Extensible: ability to add new features including transports without affecting existing applications
  • Comprehensive information modelling capabilities: for defining any model from simple to complex


“DECHEMA is the expert network for chemical engineering and biotechnology in Germany. As a non-profit professional society we represent these fields in science, industry, politics and the general public. DECHEMA promotes scientific and technical exchange among experts from different disciplines, organisations and generations. We consolidate the know-how of over 5,800 individual and sustaining members.” (https://dechema.de/en/)

DEXPI - Data Exchange in the Process Industry

“The objective of the DEXPI initative is to develop and promote a general data exchange standard for the process industry, covering all phases of the lifecycle of a (petro-)chemical plant, ranging from specification of functional requirements to assets in operation. Currently, the focus of the DEXPI initiative is the exchange of Piping and Instrumentation diagrams (P&IDs).” (http://www.dexpi.org/)

Scope of this work

The scope of this work is to extend the OPC UA standard data model with the capability of modelling and transferring the engineering information of Piping and Instrumentation Diagrams (P&IDs) that are based on ISO 15926 and the DEXPI 1.2 specification.

This companion specification is an extension of the overall OPC Unified Architecture standards and defines an information model that conforms to the DEXPI specification (which is based on the ISO 15926 standard).

The modelling targets of this standard shall exist in an OPC UA Address Space. This standard does not consider the modelling targets that are identified in other standards or vendor specifications.