Standard translator: OPC, PNO, FF, HART continue EDDL work

By Control Engineering Staff December 7, 2006

ISA SP104 Committee released Electronic Device Description Language (EDDL) “draft for ballot” this fall, part of an effort to adopt generic device description language specified by IEC 61804 for device integration. “The committee wants to work toward the adoption of the IEC 61804 standard as an ANSI/ISA standard,” said committee chair Terry Blevins. “We’re also committed to provide information that will help users and integrators fully utilize the EDDL interface to support a wide gamut of intelligent devices.”

The draft ANSI (ISA) 61804 standard covers an operating system independent language for declaring device parameters and their dependencies, device functions, graphical representations, and interactions with control devices. EDDL is used to create an Electronic Device Descriptions (EDD) file for intelligent devices to integrate these with control systems and portable tools for use in the field. These XML-like files may be used with handheld communicators, configuration software, and intelligent device management software to support information retrieval, diagnostics, performance analysis, operational statistics, parameter handling, operation, range setting, calibration trim, simulation, override, and monitoring of automation system components.

The applications of EDDL may include simple as well as sophisticated devices such as generic digital and analog input/output modules, motion controllers, human machine interfaces, transmitters, on-off and regulating valves, closed-loop controllers, encoders, hydraulic valves, and programmable controllers. Tools based on EDDL aim to enable faster device commissioning and loop checkout, as well as reducing field trips and eliminating unnecessary maintenance. Benefits from EDDL-based tools match corporate strategies such as reduced maintenance cost, quality improvement, increased throughput, and reduced downtime. Cooperating in the EDDL effort are Fieldbus Foundation , HART Communication Foundation , Profibus Nutzerorganisation e.V. , and OPC Foundation. Work includes mapping EDDL into OPC UA servers, enabling OPC UA client applications protocol independent access to FOUNDATION fieldbus, HART, and Profibus devices.

Recently approved enhancements, part of the IEC 61804 maintenance cycle, extend the capabilities of EDDL to provide an industry standard for advanced visualization of intelligent device information. The effort maintains the integrity of existing EDD technology across Profibus, FOUNDATION fieldbus, and HART. More than 15 million installed devices use EDDL, the committee says.

— Edited by Mark T. Hoske , editor in chief ,Control Engineering