communication mechanisms.

To take into account the user's desire for upgradability and compatibility, these commands will be mapped onto existing well-proven PROFINET services—in this case, onto records. These acyclic services do not occupy additional addresses in the process image. That is, the volume of user data of a PROFINET device is not altered. Thus, the new commands can be used in existing program libraries and factory standards without repercussion.

Likewise, device manufacturers can use a firmware update to expand their existing components to include the new functionality. This enables fast implementation, even in existing products.

 

High savings potential

The main benefits for the end user are the energy savings and related cost savings. The goal is to switch off non-required equipment in part or in whole. This is the focus of PROFIenergy. Users can expect to achieve savings of up to 80 percent.

Another focus is the expedient use of available energy during production. For example, certain secondary processes can be paused during production, as well. PROFIenergy is thus the basis that allows the user to manage energy efficiently.

Measures are currently available in selective cases to switch off equipment components during idle times. However, these are very application-specific. In addition, these measures often combine the actual control task and the energy management. All of these factors complicate programming and, in particular, the updating and maintenance of this type of software. In addition, the actual switching operation requires external hardware, which must be configured, installed, and maintained. The effort involved for this quickly exceeds the actual savings.

The new profile provides an economical situation in this case, as well. The switching functions are already integrated in the devices. Furthermore, there is a clear separation between the program sections for energy management and for the control logic. As a result, both sections of the program can be tested and commissioned independently. Structured programming also greatly simplifies the updating and maintenance of the user program over the long term.

Profile with value added

PROFIenergy guarantees a uniform interface for energy management. The user is thus free to choose devices from different manufacturers. He can look for the device that is best suited to his application and saves the most energy. The end user benefits from the competition among device manufacturers and system manufacturers to develop energy-saving solutions.

The goal of PI and its member companies is to adopt the PROFIenergy profile by the end of 2009. To assure the suitability of the profile for real-world applications, the work group includes representatives of device manufacturers as well as various institutes and users. In addition, the work group is in close contact with the Automation Initiative of German Automobile Manufacturers (AIDA). A few companies have already announced their plans to quickly implement PROFIenergy into their devices and a variety of customers have also expressed great interest. As a result, the first components and solutions are anticipated to become available in 2010.

Author: Norbert Brousek, Siemens AG