BS EN IEC 61158-5-2:2019

What is BS EN IEC 61158-5-2 - Application layer service type 2 elements about?  

BS EN IEC 61158-5-2 is a part of the IEC 61158 series that provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 2 Fieldbus. 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. 

BS EN IEC 61158-5-2 defines in an abstract way the externally visible service provided by the Type 2 Fieldbus application layer in terms of: 

• An abstract model for defining application resources (objects) capable of being manipulated by users via the use of the FAL service 
• The primitive actions and events of the service  
• The parameters associated with each primitive action and event and the form in which they take 
• The interrelationship between these actions and events, and their valid sequences 

BS EN IEC 61158-5-2 defines the services provided to: 

• The FAL user at the boundary between the user and the application layer of the Fieldbus 
• reference model 
• Systems Management at the boundary between the application layer and Systems Management of the Fieldbus reference model 

BS EN IEC 61158-5-2 specifies the structure and services of the Type 2 Fieldbus application layer, in conformance with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). 

Who is BS EN IEC 61158-5-2 - Application layer service type 2 elements for? 

BS EN IEC 61158-5-2 on Application layer service type 2 elements is useful for: 

• Internet service providers 
• Telecommunication companies 
• The IT industry / Software programmers  
• Internet engineering task forces  
• The automation industry 
• Networking sectors 
• Implementors and designers of industrial automation systems 

Why should you use BS EN IEC 61158-5-2 - Application layer service type 2 elements?  

BS EN IEC 61158-5-2 is one of a series produced to facilitate the interconnection of automation system components. BS EN IEC 61158-5-2 is related to other standards in the set as defined by the “three-layer” Fieldbus reference model described in IEC 61158-1. The application service is provided by the application protocol making use of the services available from the data link or other immediately lower layer.  

BS EN IEC 61158-5-2 defines the application service characteristics that Fieldbus applications and/or system management may exploit. Throughout the set of Fieldbus standards, the term “service” refers to the abstract capability provided by one layer of the OSI Basic Reference Model to the layer immediately above. Thus, the application layer service defined in BS EN IEC 61158-5-2 is a conceptual architectural service, independent of administrative and implementation divisions. Using BS EN IEC 61158-5-2 guidelines, you facilitate the creation of systems that increase the work efficiency for your customers. 

What’s changed since the last update?  

BS EN IEC 61158-5-2:2019 supersedes BS EN 61158‑5‑2:2014, which will be withdrawn on 15 May 2022. BS EN IEC 61158-5-2:2019 includes the following significant technical changes with respect to BS EN 61158‑5‑2:2014 such as: 

• Addition of a data type in 5.3.2
• Clarifications of Object management ASE in 6.2.1
• Extensions of General ASE in 6.2.1.2.1
• Extensions/clarifications of Identity ASE in 6.2.1.2.2
• Update of Message Router ASE in 6.2.1.2.4