IEC 61158-5-24:2023 PDF

Overview

IEC 61158-5-24:2023 is part of the IEC 61158 fieldbus specifications and defines the application layer service elements (ASEs) and communication model for Type 24 fieldbus systems. The standard provides common elements for both time‑critical and non‑time‑critical messaging between application programs in industrial automation. It specifies service definitions, class and AR (Application Relation) models, and conformance guidance to ensure interoperable application‑level communications among controllers, field devices and system managers.

Keywords: IEC 61158-5-24:2023, industrial communication networks, fieldbus specifications, application layer, Type 24, time-critical messaging.

Key Topics and Technical Requirements

• Application layer service definitions (ASEs):
  • Fieldbus System Manager (FSM) ASE - system-level services such as reset, status, context and start/stop operations.
  • Field Device Control (FDC) ASE - master/slave/monitor classes for device control, cycle management, connect/disconnect, data exchange and command services.
  • Message (MSG) ASE - requester/responder classes for user messages, one‑way messages, transactions and aborts.
  • Event Management (EVM) ASE - synchronization of events and network clock reading.
• Application Relations (ARs): AR models and AREP definitions for FDC and MSG AR classes describing how application programs establish and manage communication relationships.
• Service tables and semantics: Detailed service operation tables (e.g., FDC-Reset, FDC-DataExchange, MSG-UserMessage) that specify input/output parameters, expected behavior and error conditions.
• Time‑critical behavior: Clear treatment of time windows and timing certainty - actions required within defined windows and consequences of timing failures for safety, equipment and plant operation.
• Conformance & normative references: Rules for conformance testing and references to ISO/IEC foundational terms and conventions used by the standard.

Practical Applications

• Implementing application‑level communication for industrial automation systems, including PLCs, RTUs and intelligent field devices.
• Designing real‑time control systems where deterministic, time‑aware messaging is required (manufacturing lines, process control, safety systems).
• Developing device firmware and network stacks that must interoperate with Type 24 fieldbus implementations.
• Creating test suites and certification procedures for vendor compliance with application layer services.

Who Should Use This Standard

• Control system designers and integrators
• Field device and industrial network product manufacturers
• Firmware and middleware developers for industrial devices
• Test laboratories and certification bodies
• Automation architects focused on deterministic, time‑sensitive communications

Related Standards

• Other parts of the IEC 61158 fieldbus series (application, data link and physical layer specifications)
• Relevant ISO/IEC standards referenced for terms, conventions and ASN.1/data modeling

IEC 61158-5-24:2023 is essential for anyone implementing or validating application‑layer functionality for Type 24 fieldbus in safety‑ and performance‑sensitive industrial networks.