Hans Kranz on the BACtwin as a story of inevitability

All larger real estate portfolios require brand and manufacturer-independent systems for technical building and energy management. The BACnet protocol has become established among many building owners and operators for networking their technical systems. However, the protocol alone does not provide future security. The conditions for the manufacturer-neutral use of BACnet in larger real estate portfolios for energy- and cost-efficient management was the topic of a symposium hosted by ICONAG-Leittechnik GmbH at the Gutenberg Digital Hub in Mainz. Prominent figures from the building automation scene as well as operators of large real estate portfolios and planners attended the event.

Necessity of BACnet specifications

Operators who want to manage several buildings with BA systems from different manufacturers from a central location have found that it is not enough to simply prescribe the BACnet standard in accordance with AMEV or other regulations.
 

BACman Hans Kranz impressively explained the reasons for this in his keynote speech at the conference: "When the GA world standard ISO 16484 was formulated between 1995-2005, the so-called 'bus war' was raging. The lowest common denominator had to be found between Profibus, FND, LON, EIB/KNX and BACnet. And the forward-looking BACnet objects and properties did not provide for this. This created a standardization gap. As the building owners and planners did not specify the use of the BACnet objects and their properties in accordance with the applicable standard, the market cleverly used this to tie the building owner to the first supplier for extensions under the guise of BACnet. This initially made it impossible for the building owner to be independent of the brand and manufacturer.

This standardization gap is still the cause of media disruptions between client specifications, planning output, engineering and operation of BA systems. Depending on the integrator and manufacturer, clients can receive different solutions for identical systems, meaning that the potential benefits do not always materialize in practice.

This standardization gap is still the cause of media discontinuities between client specifications, planning output, engineering and operation of BA systems. Depending on the integrator and manufacturer, building owners may receive different solutions for identical systems, meaning that the potential benefits do not always materialize in practice.

The basis for information processing and digitalization, including in building automation, is information. As the "global language of building automation", BACnet provides this information with its objects and properties. In order to reduce energy costs or adapt the operating mode to requirements, this information must be interpretable. In order to ensure this for building automation across manufacturers and brands, clear specifications are required from the building owner or their planner.

"BACnet and the digital twin of building automation are therefore a story of inevitability," says Kranz. The BACtwin was developed under the leadership of Hofrat Prof. Dr. Rupert Fritzenwallner* as part of a series of "BACnet in Austria" conferences that he moderated. The GA function list (GAFL) was established as a central component in accordance with World Standard Part 3. It is available in Excel format and is accepted in the industry.

The BACtwin extends the GA function list and thus consists of 3 essential components, which are to be specified by the client or planner:

1. GA function list, which is required by the contract regulations in VOB/C DIN 18386, supplemented by

2. structured BACnet object names instead of "fuzzy" "data point addresses" and

3. specifications for the use of the required properties, i.e. the information that the building automation system can provide.

All of this together as an Excel worksheet represents the digital twin. This is the first time that the functions of a system have been combined with the information required for efficient operation, consisting of the specifications for the BACnet objects and properties. The BACtwin is an immediately applicable virtual model of the real building automation system, including its functions and information. It is suitable for the entire life cycle of the BA system.

This step is an essential further development of building automation and the BACnet standard.