IEC 61158-5-16:2007

Overview

IEC 61158-5-16:2007 is an international standard from the International Electrotechnical Commission (IEC) that defines the application layer service specifications for Type 16 fieldbus systems in industrial communication networks. This standard is part of the broader IEC 61158 series, which covers fieldbus specifications crucial to reliable, real-time automation and process control in industrial environments.

The primary goal of this standard is to provide a structured, abstract service interface-known as the Fieldbus Application Layer (FAL)-that enables user programs to communicate effectively over a fieldbus network. By defining a "window" between application programs, the FAL supports both time-critical and non-time-critical messages, ensuring interoperability and flexibility for various automation scenarios.

Key Topics

• Application Layer Service Definitions: IEC 61158-5-16 describes key services and behaviors for the application layer, including the way messages are requested, delivered, and confirmed in a standardized manner.
• Time-Critical and Non-Time-Critical Messaging: The standard distinguishes between operations with strict timing requirements (time-critical) and those that can tolerate delays (non-time-critical), both essential in safe and efficient automation.
• Object-Oriented Service Elements (ASEs): Services are structured using object-oriented elements, allowing flexible access and management of application objects, such as devices and process data.
• Data Types and Communication Models: Supports a range of fundamental data types (BitString, Integer, Float, VisibleString) and defines communication using cyclic (publisher-subscriber) and non-cyclic (client-server) mechanisms.
• Identification Number (IDN) Concept: Data and attributes transmitted between devices use standardized identification numbers, supporting straightforward and consistent data access.

Applications

IEC 61158-5-16:2007 serves as a foundational reference for:

• Industrial Automation Systems: Facilitates reliable, standardized communication in distributed control systems, where performance, safety, and interoperability are critical.
• Process Control Environments: Ensures timely data exchange for monitoring and controlling time-sensitive processes, reducing risks of application or system failure.
• Device Interoperability: Supports integration of diverse equipment-including programmable logic controllers (PLCs), drives, sensors, and I/O modules-across a unified fieldbus network.
• Flexible Integration and Migration: Provides a framework for incorporating new types of fieldbuses and migrating from legacy communication protocols to modern, standardized solutions.
• System Management and Monitoring: Enables effective access to device status, network status, and other essential parameters, supporting comprehensive system oversight.

Related Standards

For a complete implementation and integration of industrial communication networks, IEC 61158-5-16:2007 references and works closely with several related standards:

• IEC 61158-3-16 – Data-link layer service definition for Type 16 elements
• IEC 61131-3 – Programming languages for programmable controllers
• IEC 60559 – Binary floating-point arithmetic for microprocessor systems
• IEC/TR 61158-1 – Overview and guidance for the IEC 61158 series
• ISO/IEC 7498-1 – OSI Basic Reference Model
• ISO/IEC 9545 – OSI Application Layer Structure

These standards collectively ensure a robust, interoperable framework for industrial communication and automation, supporting scalability, maintainability, and international compatibility.

By adhering to the guidelines and structures defined in IEC 61158-5-16:2007, stakeholders in industrial automation can achieve consistent application layer communication, paving the way for secure, efficient, and future-ready industrial communication networks.