IEC 61158-3-4 provides common elements for basic time-critical messaging communications between devices in an automation environment. The term “time-critical” is used to represent the presence of a time window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant, and possibly human life.
IEC 61158-3-4 defines in an abstract way the externally visible services provided by the Type 4 Fieldbus data-link layer in terms of:
The purpose of IEC 61158-3-4 is to define the services provided to:
layers of the Fieldbus reference model
IEC 61158-3-4 on data-link layer service definition is useful for:
IEC 61158-3-4 is part of the industrial communication network series that has been produced to facilitate the interconnection of automation system components.
The principal objective of IEC 61158-3-4 is to provide the characteristics of conceptual datalink
layer services suitable for time-critical communications, and thus supplement the OSI Basic Reference Model in guiding the development of data-link protocols for time-critical communications.
A secondary objective is to provide migration paths from previously-existing industrial communications protocols to users.
BS EN IEC 61158-3-4:2019 supersedes BS EN 61158-3-4:2014. BS EN IEC 61158-3-4:2019 includes some technical changes with respect to BS EN 61158-3-4:2014. These include:
EN 61158-3-4:2019
IEC 61158-3-4:2019