BS EN 61158-5-20:2014

What is BS EN 61158-5-20 - Type 20 application layer service definition about?   

BS EN 61158-5-20 is part of a series produced to facilitate the interconnection of automation system components. BS EN 61158-5-20 is related to other documents in the set as defined by the “three-layer” fieldbus reference model described in IEC 61158-1. 

BS EN 61158-5-20 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 20 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 61158-5-20 defines in an abstract way the externally visible service provided by the Type 20 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 which they take 
• The interrelationship between these actions and events, and their valid sequences 

Who is BS EN 61158-5-20 - Type 20 application layer service definition for? 

BS EN 61158-5-20 on industrial communication networks is useful for: 

• 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 61158-5-20 - Type 20 application layer service definition?  

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 61158-5-20 defines the application service characteristics that fieldbus applications and/or system management may exploit. 

BS EN 61158-5-20 defines the services provided to the FAL (fieldbus application layer) user at the boundary between the user and the application layer of the fieldbus reference model. 

BS EN 61158-5-20 specifies the structure and services of the IEC fieldbus application layer, in conformance with the OSI basic reference model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). 

Overall, the guidelines of BS EN 61158-5-20 help you to gain a better understanding of the type 20 fieldbus application layer, this can help you to integrate it into your industrial communication networks and thereby enhance their efficiency.