Endress+Hauser, in collaboration with Covestro, BASF and Yokogawa, completed a large-scale Ethernet-APL scalability test designed to evaluate the technology in complex, multi-vendor process automation environments.

The testing, conducted in May at Endress+Hauser Digital Solutions in Reinach, Switzerland, integrated a Yokogawa CENTUM VP distributed control system and Plant Resource Manager with Ethernet-APL field devices, switches and network infrastructure from multiple suppliers. According to the companies, the objective was to validate interoperability and long-term stability under conditions designed to simulate large chemical manufacturing environments.

Unlike previous large-scale tests that focused primarily on device density, this program evaluated Ethernet-APL across more complex plant architectures, including multiple Ethernet-APL ring topologies, cross-vendor distributed control systems and multi-day testing to evaluate network stability.

The validation was led by Covestro, with BASF contributing experience from earlier Ethernet-APL scalability demonstrations.

"Ethernet-APL is a key element on our digital transformation journey — it extends high-speed communication into the field, unlocking the data transparency and connectivity needed to fully digitalize our operations," said Sebastian Mahler, vice president and head of process control technology at Covestro, in a statement. "Taking an active role in this scalability test allowed us to validate the technology under conditions that closely reflect the complexity of our real production environments. The results give us greater confidence in the technology's readiness for deployment in large-scale industrial environments."

The latest testing builds on previous Ethernet-APL scalability demonstrations. According to BASF, earlier testing connected 240 PROFINET over APL devices in a single Ethernet ring using distributed control systems from ABB, Honeywell and Siemens. Emerson joined the interoperability testing in 2025, while the 2026 program added Yokogawa's CENTUM VP platform.

The latest validation reflects broader adoption of Ethernet-APL across the process industries. The technology enables high-speed Ethernet communications between field devices, distributed control systems and enterprise applications over a single network architecture, improving interoperability, diagnostics and asset management while reducing network complexity. Earlier this year, Chemical Processing examined how the technology is helping simplify digital field communications in process plants.