Page 96 - Industrial Plants

Ethernet terminology

Ethernet. Communications Protocols for Process without gateways. The Physical Layer The physical
Industries Ethernet-APL transports any type of layer is the infrastructure that transports the signal and
protocol. In process industries, the most prevalent are provides power. Ethernet-APL is the ruggedized
Ethernet-IP, HART-IP, OPC/UA, or PROFINET. The version for the field. Standard Ethernet, Fast Ethernet,
protocol defines the contents and structure of data and or Gigabit are also physical layers for Ethernet, and so
information. E.g. industrial protocols define signals like is the entire range of single-pair Ethernet (SPE). Layers
an analog input, warning message, safety 1 and 2 of the ISO/OSI model define the physical layer.
communication, etc. Other protocols such as the There is complete freedom to design and implement
HTML protocol (layer 7) describe what a web page topologies with Ethernet-APL, the most popular being
looks like and how to collect user input via forms. The star and the trunk-and-spur. FieldConnex switches
FieldConnex switches provide easy access to status, connect Ethernet-APL networks to higher-level
configuration, and diagnostics via a web browser. networks. The solutions for installation and junction
Devices do the same. Protocols facilitate other tasks. boxes are similar to Fieldbus. Similarities and
There are specialized protocols for network Differences to Fieldbus Process Fieldbus systems such
management, port identification, and more. An as Foundation Fieldbus H1 and PROFIBUS PA are
Ethernet-based system enables any device or system complete definitions of physical layer and protocol.
to access another device or system concurrently and They incorporate both, a protocol definition and a
physical layer definition. Manchester Bus Powered
(MBP) is the name of the physical layer according to
IEC 61158-2. Ethernet-APL is designed to utilize cable
type ‘A’ saving on installation cost. With Pepperl+Fuchs
patented technology and switches, users can naturally
operate Ethernet-APL and Fieldbus devices on the
same infrastructure. Many benefits of MBP are also
incorporated into the design of Ethernet-APL. They
are:
• Power and communication on a two-wire cable,
type ‘A’.
• High-Power Trunk-and-Spur topology.
• Same easy validation of intrinsic safety, called
2-WISE.

INDUSTRIAL PLANTS - May 2022
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