IEC 61804-4:2015

Overview

IEC 61804-4:2015 is an international standard established by the International Electrotechnical Commission (IEC) that specifies the interpretation of Electronic Device Description Language (EDDL) for function blocks used in process control and electronic device descriptions. This standard aims to enable consistent implementation and interoperability of EDDL applications by providing detailed guidance on how Electronic Device Descriptions (EDD) should be interpreted by software applications. It supports improved portability of device descriptions between different EDDL-compliant applications, ensuring seamless integration and consistent user experience in process automation environments.

This edition, published in 2015, represents a technical revision and update from the earlier IEC TR 61804-4 (2006). It incorporates important new elements such as enhanced data description, method programming, offline and online device configuration, and extended user interface descriptions tailored for EDDL tools.

Key Topics

• EDD Interpretation Consistency: Defines how EDD applications must consistently interpret EDDL constructs to promote interoperability.
• EDDL Data Description: Introduces structured data representation, including variables and data classes that describe field devices in detail.
• EDDL Method Programming: Specifies the use of inbuilt functions and methods within EDDL for dynamic device control and interaction.
• User Interface Descriptions: Establishes standard menu conventions and layout rules for handheld and PC-based EDDL applications, enhancing usability.
• Offline and Online Configuration: Details procedures for configuring modular devices both offline and live within the system for flexible device management.
• Modular Device Support: Addresses modular and multi-component devices, detailing instance object models, component relationships, and upload/download mechanisms.
• Edit Sessions and Data Management: Specifies data caching, dialog management, user roles, and transactional operations to maintain data integrity during configuration editing.
• Communication Description: Defines protocols for command execution, transaction handling, and message parsing critical for reliable device communication.

Applications

IEC 61804-4:2015 is highly relevant for:

• Field Device Developers: Ensures that device descriptions in EDDL are developed consistently, adhering to interoperability requirements.
• Automation Software Vendors: Provides a framework for building EDDL viewers, editors, and configurators that accurately interpret device descriptions.
• Process Control System Integrators: Facilitates seamless integration of diverse field devices with host control and asset management systems by standardizing device description interpretation.
• Manufacturers of Modular Devices: Supports development, configuration, and diagnostics of modular and multi-component devices employing EDDL.
• Maintenance and Operation Teams: Improves device management through standardized user interfaces for handheld tools and PC applications, enabling efficient diagnostics and configuration changes.

By adopting this standard, stakeholders achieve improved portability of device descriptions across different software platforms, consistent device behavior, and reduced engineering time in process automation projects.

Related Standards

IEC 61804-4:2015 is part of the IEC 61804 series related to function blocks for process control and EDDL. Key related standards include:

• IEC 61804-1 - General framework for Function Blocks (FB) for process control.
• IEC 61804-2 - EDDL specification – Device description language syntax and structure.
• IEC 61804-3 - Guidelines for FDI (Field Device Integration) combining EDDL and FDT technologies.
• IEC PAS 62541 - OPC Unified Architecture standards often used alongside EDDL for communication.
• IEC 61131 - Programmable controllers standards relevant to process control applications.

Implementing IEC 61804-4 in harmony with these standards promotes consistency in field device descriptions, functional interoperability, and coherent asset management practices in industrial automation systems.

Keywords: IEC 61804-4, EDDL interpretation, Electronic Device Description Language, function blocks, process control, field device interoperability, modular device configuration, offline and online configuration, automation standards, device description portability, process automation standards.