Skip to main content

Looking for long-term stable technology   

Process plants operate for 20+ years and are required to be safe for people, the product, and the environment. Explosion potential in hazardous areas and harsh conditions require that any deployment of new technology is both thoroughly tested and provides added business benefits. Ethernet is the de-facto communication standard in enterprises, but it does not meet the requirements in the field of process automation without modification. Ethernet with an Advanced Physical Layer (Ethernet-APL) will enable long cable lengths and explosion protection via intrinsic safety with communication and power over two wires. Based on IEEE and IEC standards, Ethernet-APL supports any Ethernet-based automation protocol and will develop into a single, long-term stable technology for process plants.

The agreement to develop the Ethernet-APL technology under “The APL Project” was established in 2018 and is backed by the leading industry standard development organizations (SDOs) FieldComm Group, ODVA, OPC Foundation, and PROFIBUS & PROFINET International, as well as by major industry suppliers of process automation, including ABB, Emerson, Endress+Hauser, Krohne, Pepperl+Fuchs, Phoenix Contact, R. Stahl, Rockwell Automation, Samson, Siemens, Vega, and Yokogawa.



Ethernet-APL reaches intrinsic safety protection

Ethernet-APL is an enhanced physical layer for single-pair Ethernet (SPE) based on 10BASET1L. It communicates via a cable length of up to 1000 m at 10 MBit/s, full-duplex, which is more than 300 times faster than current technologies, such as HART or fieldbus. It is the logical extension for Ethernet and provides the attributes required for reliable operation in the field of a process plant. Ethernet-APL is a physical layer that will be able to support any higher-level Ethernet protocol including PROFINET. Communications are based on 10BASE-T1L as defined in IEEE Std 802.3cg-2019, which is being adopted by suppliers serving many market segments in building and industrial automation. Ethernet-APL includes additional attributes required by process applications. The requirements result from outdoor installations and explosion hazardous area protection beyond the long cable lengths. The additional electrical features follow the IEC technical specification, IEC TS 60079-47 (2-WISE), which defines intrinsic safety protection for all hazardous Zones and Divisions. For users, this includes simple steps for verification of intrinsic safety without calculations. 2-WISE stands for 2-Wire Intrinsically Safe Ethernet. “The APL Project” creates the concept of Ethernet-APL by defining port profiles for multiple power levels with and without explosion hazardous area protection. Ethernet-APL allows wiring to screw-type or spring-clamp terminals, thus supporting cable entry through glands. Additionally, well-defined connector technology ensures simplicity during installation work.

general Ethernet-APL architecture
The general architecture of the enhanced physical layer for single-pair Ethernet (SPE) based on 10BASET1L, called Ethernet-APL.

What makes Ethernet-APL unique

Ethernet-APL is designed to support various installation topologies, with optional redundancy or resiliency concepts and trunk-and-spur. Ethernet-APL explicitly specifies point-to-point connectionsonly with each connection between communications partners constituting a “segment”.


Find out more details in the Ethernet-APL White Paper.

Our well-known PI technologies


PROFIBUS is a standardized, open, digital communications system for all areas of application in manufacturing and process automation.


PROFINET is the innovative open standard for Industrial Ethernet. It satisfies all requirements of automation technology.

IO-LINK is an independent sensor / actuator interface solution for use with all automation technologies.



Omlox is an open technology standard for real-time indoor localization systems for industrial manufacturing.