DDL - Long Term Solution

Today more than 1000 device types of about 100 manufactures are described with DDL. In plants about 15.000.000 devices are in use. A DD is an operating system independent text file. The DD stores device information. The first DD’s developed in 1992 can still be used today without change. This shows the stability of the DDL technology.

The Compnents of a DD

In the first part DD contains information about the manufacturer, the device type, the device revision und the DD revision. This is used for identification and version control. The main part contains the description of the user interface, the data and the communication.

Description of the user interface

The user interface is defined with menu descriptions. So it’s easy to build hierarchies of menus, dialogs and parameter

Online Configuring

DDL allows for the description of online dialogs to display device parameters. The user can change writeable parameters and download them to the device.

	Graphical Representations
It is possible to display parameters in charts. Therefore, necessary parameters have to be listed in the DD. If the DD application does not support the output of charts, it will display the parameters numerically.

HART® is a registered trademark of the HART Communication Foundation