Nov 1, 2014 - Building
It´s the Combination!
“Hammerbrook Höfe”, the headquarters for Deutsche Bahn, is located in Hamburg, Germany directly on the Mittelkanal near the Elbe River. The grounds, where the building complex now houses the offices for 950 employees, were left vacant after being destroyed by bombs during World War II. It is now graced with a modern building that has minimal environmental impacts thanks to its energy-saving design. The automation experts at Samsomatic in collaboration with WAGO made important contributions to help turn the design into a reality.
The once-empty building in Hamburg has been teeming with life since January 2013. The 110 m long complex includes modern conference technologies, an employee restaurant, roof terraces, a parent-child center and green spaces. It is definitely a prestige project — and also an interesting challenge for building automation. The automation technology used had to correspond to the unusual complexity of the building.
One glance at the numbers makes it clear why the project could not be realized just by using standardized solutions. A few examples: EnOcean room control units based on radio technology were used to regulate the climate in the 610 spatial zones, with 1,250 MP-Bus valve actuators required for temperature control alone. At the same time, the 1,100 window contacts and blinds are controlled via the KNX bus, the 250 volume flow regulators with M-bus and the 750 associated lights using a DALI bus. On top of all of this, the automated monitoring of 600 fire protection dampers and 750 condensation monitors were also connected to the system. In total, that comes to around 14,000 data points. This also means that the technical solution was tasked with unifying a correspondingly large number of bus systems from every sector of building automation. Samsomatic GmbH from Frankfurt am Main, Germany won the building technology contract and brought the specialists from WAGO on board for individual room control.
One Solution for the Most Demanding Scenarios: WAGO-I/O-SYSTEM 750
Together the building automation experts from the two companies developed a suitable, tailored design that met the project’s demands. It was based on the proven WAGO-I/O-SYSTEM 750, which is flexible and makes the most of compact spaces thanks to finely modular designs that can readily adapt to specific requirements. The system is also fieldbus-independent, meaning it can communicate with all the necessary bus systems. “In all, there are 55 system distribution boxes in the building using the WAGO-I/O-SYSTEM 750 that operate all of the necessary interfaces,” reports Eckhard Callies, Manager of Building Automation at Samsomatic. “That is how we succeeded in realizing a compartmentalized automation structure.”
The WAGO system distribution boxes serve as communication nodes at Hammerbrook Höfe. “The space determined the requirements,” Callies explains. “The building is divided into nine zones that are based on room function; these zones are controlled using system distribution boxes in four standardized equipment versions.” The distribution boxes use various bus systems, including DALI, MP-Bus, KNX and EnOcean, for controlling the individual rooms — they communicate with lights, blinds, valve actuators and other components in the offices, conference rooms and kitchenettes. The information collected at the distribution boxes is then transmitted via BACnet/IP to one of 17 higher-level central control cabinets that exchange data with the building automation system via ETHERNET.
Hybrid Cooling Ceilings for Energy-Efficient Heating and Cooling
One of the most important functions in individual room control is heating and cooling. At Hammerbrook Höfe, a hybrid cooling ceiling is used that is controlled from the system distribution box via MP-Bus. This solution is comprised of a radiant cooling ceiling and concrete core activation. Water flows through cooling and heating panels in the areas above the suspended ceiling. The water, which is usually heated to approximately 17 °C, flows through copper serpentine piping that is connected to the slab roof via thermal conduction rails. This massive component then absorbs or emits heat from or to the water, depending on whether heating or cooling is needed. Due to the comparatively large transfer surface, the temperature differences can be quite small. This means that the water does not require much heating when warmth is desired. The use of this type of solution has a number of advantages; however, above all, it is a very energy-efficient system. In addition, there are no uncomfortable drafts; the cooling ceilings ensure optimum ventilation and also absorb noise, enabling them to make another positive impact on the office spaces.
Although individual settings are not generally needed due to the centrally controlled cooling ceilings, employees still have control over the temperature in individual rooms. For this, EnOcean operating panels in the rooms communicate with the system distribution boxes.
Other aspects besides temperature are also important for optimum working conditions. That is why the building automation also controls blinds in the complex, automatically setting them according to the time of day, light ratio and angle of the sun. This creates ideal shading in the rooms and keeps them glare-free. In addition, the system distribution boxes control the 750 lights in the building using the DALI-Bus. As soon an occupant sends a command using the control panel, it is forwarded via KNX to the distribution box that controls the lights using DALI-Bus. Light timers and presence sensors also ensure that the hallway lights are not left on at the end of the day.
In addition to all these functions, WAGO’s technology even contributes to making conference rooms more pleasant during longer meetings. The conference rooms have air quality sensors that provide information to the system distribution boxes to optimize control of the primary ventilation system, making the rooms' climate markedly more comfortable. In total, the building is equipped with 250 volume flow regulators that are controlled by WAGO technology using the MP-Bus. “This way, the employees don't run out of air during a longer presentation,” jokes Callies. “If there isn't enough oxygen in the rooms, then the amount of fresh air is increased by the volume flow controller.” Beyond comfort, the monitoring of 600 fire dampers and 700 condensation monitors creates a feeling of security.
The intelligent building automation from WAGO and Samsomatic is also responsible for energy consumption at Hammerbrook Höfe being below the requirements for new construction per an Energy Savings Ordinance. The project scope for Samsomatic GmbH extended to all building automation, thus it included centralized building control technology in addition to regulating individual offices and spaces. Samsomatic's proprietary automation system, Trovis 6600 with its 16 substations, has taken on this important task. In addition to a smooth system integration of the WAGO components, the success of the project resulted from a collaboration between equal partners. As Callies recalls, “That was our first joint project with WAGO here in the north. Yet from the beginning, we worked together like a long-standing team. There was intensive training for our employees, and the WAGO solutions readily adapted to our automation system. We brought the project in on deadline and within budget, and since commissioning, we have averaged fewer service calls than normal. We will definitely work with WAGO again on these types of complex projects in the future. We're a great combination!”
- 55 custom-tailored distribution boxes are the foundation for the building automation.
- Communication via all required bus systems, e.g., DALI, MP-Bus, KNX, Enocean and BACnet/IP.
- Intelligent control of heating, cooling, ventilation and shade.
Text: Stephan Lampe, WAGO
Photo: Samsomatic, Hauke Hass/vor-ort-foto.de