BS EN IEC 61158-4-24:2019

What is BS EN IEC 61158-4-24 - Data link type 24 elements about?  

BS EN IEC 61158-4-24 is part of the BS EN IEC 61158 series that has been created to facilitate the interconnection of automation system components. The data-link layer provides basic time-critical messaging communications between devices in an automation environment. BS EN IEC 61158-4-24 provides communication opportunities to all participating data-link entities: 

• In a synchronously-starting cyclic manner, according to a pre-established schedule 
• In an acyclic manner, as requested by each of those data-link entities 

BS EN IEC 61158-4-24 is characterized as one which provides cyclic and acyclic access asynchronously but with a synchronous restart of each cycle. 

BS EN IEC 61158-4-24 specifies: 

• Procedures for the timely transfer of data and control information from one data-link user entity to a peer user entity, and among the data-link entities forming the distributed datalink service provider 
• Procedures for giving communications opportunities to all participating DL-entities (DLEs), sequentially and in a cyclic manner for deterministic and synchronized transfer at cyclic intervals up to 64 ms 
• Procedures for giving communication opportunities available for time-critical data transmission together with non-time-critical data transmission without prejudice to the time-critical data transmission 
• Procedures for giving cyclic and acyclic communication opportunities for time-critical data transmission with prioritized access 
• Procedures for giving communication opportunities based on ISO/IEC/IEEE 8802-3 medium access control, with provisions for nodes to be added or removed during normal operation 
• The structure of the Fieldbus DLPDUs used for the transfer of data and control information by the protocol of BS EN IEC 61158-4-24, and their representation as physical interface data units 

Note: The 'colour inside' logo on the cover page of this publication indicates that it contains colours that are considered to be useful for the correct understanding of its contents. Users should therefore print this document using a colour printer. 

Who is BS EN IEC 61158-4-24 - Data link type 24 elements for? 

BS EN IEC 61158-4-24 on Data link type 24 elements 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 IEC 61158-4-24 - Datalink type 24 elements?  

BS EN IEC 61158-4-24 is produced to facilitate the interconnection of automation system components. It is related to other standards in the set as defined by the “three-layer” Fieldbus reference model described in IEC 61158-1. The data-link protocol provides the data-link service by making use of the services available from the physical layer. BS EN IEC 61158-4-24  provides a set of rules for communication expressed in terms of the procedures to be carried out by peer data-link entities (DLEs) at the time of communication. These rules for communication are intended to provide a sound basis for development in order to serve a variety of purposes: 

• As a guide for implementers and designers 
• For use in the testing and procurement of equipment 
• As part of an agreement for the admittance of systems into the open systems environment 
• As a refinement to the understanding of time-critical communications within OSI 

BS EN IEC 61158-4-24  focuses on the communication and interworking of sensors, effectors and other automation devices. By using BS EN IEC 61158-4-24  together with other standards positioned within the OSI or Fieldbus reference models, otherwise incompatible systems may 

work together in any combination. Using BS EN IEC 61158-4-24 guidelines, you are in a position to facilitate industrial automation that accelerates productivity. 

What’s changed since the last update? 

BS EN IEC 61158-4-24:2019 is the second edition that supersedes EN 61158-4-24:2014 and is identical to BS EN IEC 61158-4-24:2019. The technical changes as compared to the first edition published in 2014 are: 

• Patent declaration in the Introduction 
• Corrections on transmission sequence of fixed-width time slot type in 4.3.2 
• Technical extension for band sharing between I/O data exchange and message communication 
• Spelling and grammar