FDT Adds .Net Support

Implementation of digital fieldbus networks—especially Foundation Fieldbus, Hart and Profibus PA—provides a method for moving that data from the device to an asset management system. The critical part of the whole system is displaying the information for a variety of users in such a way that critical information on each device is displayed so that the unique benefits and features of each manufacturer’s devices are available to the viewer, while still being shown in a standard format that isn’t confusing to the viewer.

Last month’s Technologies department (September 2010, p. 16) discussed one of the major technologies that handle this visualization chore—Electronic Device Description Language (EDDL). This month, we take a closer look at the other major technology—Field Device Type/Device Type Manager (FDT/DTM). The most striking difference between the two is that EDDL is text-based, while FDT is built upon Microsoft Windows.

FDT has been approved as ISA 103, a standard promulgated by the International Society of Automation. International approval as IEC 62453 promulgated by the International Electrotechnical Commission is anticipated shortly. FDT Group North American Marketing Director Shannon Foos reports that negotiations have advanced to a “serious stage of discussion” to open an FDT certification center in North America. She further reports that a spring conference is in the works to bring people together to learn about the latest advances in the technology.

Building upon a Microsoft Windows foundation, FDT as it now exists uses the older Component Object Model (COM) and Distributed COM technologies. Technologists at FDT Group have been working on an update that will move its technology to the current Microsoft .Net platform, leaving COM/DCOM behind. The FDT Group has released a draft of this FDT 2.0 standard in order for its membership to begin the review process. FDT 2.0 has also reduced the number of interfaces by nearly 50 percent in order to make it easier to develop and maintain FDT-based applications.

Users were slow to migrate to Microsoft Corp.’s Windows Vista. But the latest release from the Redmond, Wash.-based software giant—Windows 7—is a different situation. The latest release is reportedly easier to use, and stocked with new features. Most importantly, it drops support for COM/DCOM.

FDT Group technical committee member Michael Gunzert, in Karlsruhe, Germany, recommends for those upgrading to the latest Windows version to check all application software and see if it has been tested or re-released for Windows 7. Those using FDT should likewise check with frame application vendors to see if their products have been qualified and re-released for the new operating system. Gunzert notes that hardware drivers are quite likely affected and should be checked. “Vendors of FDT are updating and testing, and updating and releasing now. The first of these are on the market already, with others to follow in the next month.”

Genzert adds, “The new spec is based completely on .Net, so it is possible to make use of it for frame applications and for DTMs. Some benefits include a better and more convenient user interface, improved product specifications and better performance. It also includes support for additional requirements from factory automation—support for tools and configuration of programmable logic controllers (PLCs), for example. And we have designed in some security features to protect from malicious software. DTMs must be signed, and this can be checked automatically for developers. The new spec makes it easier to develop products by incorporating the latest development tools from .Net. Plus, this technology’s simplified architecture makes it easier to build client/server applications.”

Gary Mintchell, [email protected], is Editor in Chief of Automation World.