ODVA Ethernet-APL and PA-DIM Commitments Support Open Automation

Summary

The presentation and announcements at the ODVA SPS Press Conference on Nov. 8, 2022, illustrated actions contributing to elements needed to meet the goals of open systems initiatives including NAMUR Open Architecture (NOA), Open Process Automation Forum (OPAF) Open Process Auto­mation Standards (O-PAS), and FDT Group.
 

Ethernet-APL

ODVA conformance testing is now available for EtherNet/IP network-enabled devices that communicate over the Ethernet-APL physical layer. Conformance testing verifies the Ethernet-APL physical layer functionality of EtherNet/IP by checking that the different port types properly adhere to the relevant specifications. This supports the cooperative agreement made in 2018 between the ODVA, Profibus & Profinet International, FieldComm Group and OPC Foundation.

Ethernet-APL is a ruggedized, two-wire, loop-powered Ethernet physical layer that uses 10BASE-T1L plus extensions for installation within the demanding operating conditions and hazardous areas of process plants to directly connect field devices. Ethernet-APL enables process industries to benefit from the integration of the entire process manufacturing business including automation, OT and IT systems. Ethernet-APL configurations include intrinsically safe circuits suitable for Zone 0, Zone 20 or DIV 1 installations.

Since Ethernet-APL is logically ethernet any industrial network protocol devices electrically conforms to 10BASE-T1L Ethernet physical layer standard (IEEE 802.3cg-2019) can take advantage of this physical layer.
EtherNET/IP, Profinet, and other protocols can run simultaneously on an Ethernet-APL network as they do today on standard ethernet with the same bandwidth and latency issues.

PA-DIM Collaboration

ODVA joined ongoing collaboration work on the specification for a standardized Process Automation Device Information Model (PA-DIM). The stated goal is collaboration to simplify integration of OT and IT systems by optimizing process automation end users’ management of data from field devices.

PA-DIM allows for protocol agnostic communication of common process automation instrument parameters, automation instrument parameters, including semantic IDs as defined by IEC 61987, using OPC UA information models. Eliminating automation protocol dependencies simplifies the integration of IT and OT systems. Including semantic device information enables unambiguous machine-to-machine (M2M) communication. Fieldbus-specific implementations are converted into the address space of the PA-DIM Information Model. PA-DIM allows integration across communication protocols meeting the requirements of the NAMUR Open Architecture (NOA).

Understanding semantic identification

One of the principle benefits of PA-DIM is the ability to “map” protocol specific parameters to globally standardized terms for these parameters.

PA-DIM is a manufacturer independent Information Model with a structured hierarchy for standardized data access for devices. A Device (Asset) has Set of Signals (Functions) e.g. Process Variables, which are based on OPC UA Part 100 Devices (DI-model). PA-DIM re-use IVendor-, ITag- Nameplate and IDeviceHealth- Interfaces from DI. In addition, PA-DIM defines IAdministration- and ISignalSet- Interface, so that it is reusable by other Information Models. All parameter are defined in IEC 61987 CDD with Semantic ID (IRDI), which ensures that parameter can be easy re-used between different software tools and protocols.

Another main part is the SignalVariableType, which is an extension of OPC UA Part 8: Data Access an describes analog and discrete variables including its simulation. This variable can be used at any object also from oter Information Models. The PA-DIM SignalType Object uses the SignalVariableType and adds the SignalTag and specific methods like ZeroPointAdjustment or AutoAdjustPositioner.

PA-DIM simplified data access

• Manufacturer independent
• Sorted
• Structured hierarchy
• Prioritized
• Mapping can be understood by standard interface tools

• Monitoring of field devices, process analyzers, electrotechnical equipment, …
• Plant or fleet management of mechanical equipment
• Accessing additional data and/or implementing additional measurements for process optimization
• A high-level overview of the concept can be found in the pdf.

Participating organizations share ownership of the specification and collaboratively participate in the PA-DIM working group, hosted at the FieldComm Group, creating enhancements and extensions to the PA-DIM specification. Co-owners of the PA-DIM specification include ISA100 WCI, ODVA, PROFIBUS/PROFINET International, NAMUR, VDMA and ZVEI.

Cybersecurity

Included in the event presentation was discussion of the first whitepaper of the joint Industrial Ethernet Security Harmonization Group (IESHG) formed by the OPC Foundation, PI, ODVA and FieldComm Group. The IESHG meets on a regular basis to discuss security topics in the industrial automation context. The goal of the working group is the alignment of industrial ethernet security concepts, so that end users of the protocols have less complexity when using security in their automation systems. The whitepaper was created to shed light on different topics of the security concepts of industrial automation environments. General concepts are explained in an FAQ, like Public-key infrastructures, the different certificate types of the SDOs, as well as certificate management tools. The document can be downloaded here.