OPC-UA usually stands for Open Platform Communications Unified Architecture and the standard is for data exchange as an independent platform architecture. Once the technical work is ended, the interoperable and manufacturer-independent fail-safe communication was guaranteed from the field to machine-machine communication. In Industry 4.0, the core requirements are modularization and interoperability.
In favour of OPC UA, PROFIBUS & PROFINET International were in support of it as it was an open, cross-manufacturer standard in machine-machine communication. In order to summarize the technology, fail-safe communication was designed with no standard at the machine level. The specification was solved as per OPC Unified Architecture: Safety which was a joint development by the OPC Foundation and PI. The driving force behind the technology of Fieldbus introduction was due to the modularization of the systems. This resulted in the development of individual machines that are independent of one another and started together only on the system.
The starting block of the technology is with OPC UA which enabled cross-manufacturing networking between machines, irrespective of the Fieldbuses that are used within the machine. The only problem with OPC UA is that it failed to transfer fail-safe data in comparison to Fieldbuses with PROFIsafe. By using direct cabling or couplers, safety functions were conventionally carried out.
The effort was increased and the flexibility was reduced. The gap has been closed with PI together with the OPC Foundation and the technical work on OPC UA safety was completed. Case studies related to the OPC UA Safety’s new feature has been demonstrated with secured addresses from the simplified administration for series machines. The communication is possible with different partners over the same communication during runtime. An OPC UA in further as a mapper for pub/sub has been specified for implementing security functions with demands that are high on the response time.