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DDL- Use and Benefits

What DD's Really Do?
The HART Protocol operates in a host/slave environment where an instrument is queried and responds to a host. HART has a command structure that allows device manufacturers a great deal of latitude on designing a device. All HART devices must have a minimum command set in order to be compliant. These commands are called Universal commands. Devices may also have a number of optional commands called Common Practice Commands, Many devices implement manufacturer specific commands called Device Specific Commands. The DD allows access to all commands. DD aware host systems can then use the data and display it as the user desires.

Device Description Language (DDL) is a language to describe devices. A device description (DD) is created as a text file and then translated into a standard binary file. Similar to the presentation of HTML that is independent of an operating system and browser, a DD is displayed with a DD application.

Device Integration
The DD will be developed by the device manufacturer or a service partner. DDs are distributed by the HART Communication Foundation on a disk and via the internet (download).

Benefit of DDs for ...

... customer

unified:

- User interface
- User guidance
- Multi language support
- Device integration
- Consistent online device help

Low cost for user training
Safe operation
Available for many devices
Protection of Investment
One tool for all devices and all usages
Validation of all inputs
High level of quality
Low cost for maintenance
Reduction of overall costs

... device manufacture

Suitable for simple and complex devices

- Efficient development of the DD - Easy to learn (device developer can implement the DD by himself)
- The DD and the device can be tested with the DD application

Protection of the Investment

- Stable DD standard
- Operating system independent
- Easy to expand

Reduction of cost

The DD will offer several benefits throughout the lifecycle of the plant.

Engineering

Configuring of networks, gateways and Remote I/Os
Export / Import of device data
Upload / Download
Offline configuring
Comparison of parameter

Commissioning

Address setting
Visualization of process data
Simulation
Calibration, Adjustment
Online configuring
Identification of devices for a life list

Runtime

Displaying device and diagnostic states
Support of device exchange
Identification check

Asset Management

Device state for maintenance, repair and fault removal

User Profiles

For the maintenance engineer reduced access to the device parameters
For the specialist full access to the device parameters
For device specific user profiles

Online Help and Documentation

Variables, Dialogs, Methods
Value ranges, default values, units

Catalog and e-Commerce

Order Information
Process connection
Information about Manufacturer

Usage of devices which are described with DDL

Manufacture and process industry
Maintenance, repair and fault removal in the plant or shop floor
Large installations and single device usage
Simple to complex devices
Configuration of network and PCs

Classes of Devices:

Sensors e.g. for pressure, temperature, flow, level, gas and liquid analysis
Actors e.g. positioners, switchgears, close loop controller, motor management systems
Remote I/Os
Gateways with standard communication protocols