Lighting control for Zurich's new landmark using KNX presence detectors

The Andreas Tower, with its 22 floors and a height of 80 metres, is the new landmark above Oerlikon railway station. From this place, also Amstein + Walthert AG has an outstanding view. They are anchor tenants in the new building, for which they were involved as
general contractor by supplying the modern building technology. Thanks to around 540 intelligent KNX passive infrared presence detectors from ThebenHTS, employees will have the right light in any environment.



  • Efficient lighting control
  • Sensible and fully automatic building control, which at the same time allows and considers individual user settings
  • Optimum integration of lighting into the KNX-based system


  • Presence detector theRonda P360 KNX UP WH
  • Dividing the detection areas into different zones
  • Passageways with long time delay and dimming function
  • Presence detector theRonda P360 KNX with individually adjustable detection angle
  • 2 channels light and 2 channels presence
  • Adaptable 1-channel light measurement
  • 2 individually configurable presence channels

Andreas Tower, Zurich

Modern offices and conference rooms, but also corridors and entrance areas are furnished with increasingly efficient lighting concepts – mostly based on LEDs. Presence detectors make a valuable contribution to increasing efficiency and user-friendliness. They detect persons present on the basis of slightest motion and control the lighting arranged individually or in groups independently of daylight and time of day. Especially in the prestigious SBB Real Estate project of the Andreas Tower in Oerlikon, maximum comfort played a central role in meeting the high demands of planners and users. "We definitely wanted to install state-of-the-art technology for this purpose," says Willi Rohner, member of the executive board of Amstein + Walthert AG and head of the electrical division. State-of-the-art technology also
means regulating the lighting in the fully automatic building control as autonomously as possible. The standardised office workplaces are therefore equipped with standard lamps and integrated controls, which respond to motion and daylight. In passageways, corridors, conference rooms and ancillary rooms, on the other hand, presence detectors operate depending on the setting of reference values, regardless of the light sources. They are rather based on the processes of the employees. "As a result, the lighting control is optimally
tuned to the entire KNX-based system in the Andreas Tower," says Mr Rohner.


Lighting control with proven KNX technology

The lighting concept was implemented by Melcom AG in Wallisellen, which specialises in electrical installations. In spring 2018, their experts made a first sampling with specific products from ThebenHTS and prepared the planning with the corresponding data sheets. As KNX technology was already planned in the basic configuration for all installations, its use for lighting was quite obvious, says Melcom project manager Stephan Breitenstein. A decisive factor in the selection of suitable presence detectors was their ability to reliably detect
all detection areas in the individual zones of the Andreas Tower and to blend in harmoniously with the unobtrusive architecture and ceiling structure. In the end, three ThebenHTS presence detectors made it into the final selection. The largest share of the project involves
theRonda P360 KNX UP. Each presence detector covers a distance of over 24 metres and an area of around 450 square metres. The system is especially suited for mixed light measurement for LEDs, fluorescent lamps (FL/PL/ESL) and halogen lamps.


Functional specification as project basis

Comprehensive functional specifications for the basic installation were the foundation for the smooth progress of the project. They mainly specified the detection angles and setting conditions, as well as the procedure for lighting. In passage zones, for example, presence detection uniformly dims up and maintains the level for 10 to 20 minutes, until it is automatically dimmed down again to the specified general lighting level. In this project, energy efficiency had to be subordinated to comfort. This is, for instance, shown by the fact that the corridor lighting is never completely switched off. Nonetheless, energy is saved in comparison with traditional lighting, as the brightness of the lighting varies, depending on the presence of people.


Smooth assembly, installation and programming

Delivery, assembly, connecting and programming work were carried out entirely by Melcom AG. Since there were no structural changes, the work was completed on schedule. The acceptance of the finished system also took place on schedule in August 2018.


Lighting as a wellness package

For Melcom project manager Stephan Breitenstein, the presence detectors from ThebenHTS are a valuable building block for the success of the project: "The price-performance ratio of the detectors as well as the reliability and durability are simply outstanding. The product range also offers suitable solutions for special cases." ThebenHTS sales consultant Martin Hess is certain that the project will remain a success story in the long term. "It is of course a great pleasure for us to see our products being used in this prestigious architectural
building and that they will continue to shape it over time." Client Willi Rohner and his planning team are also completely satisfied with the result. "A modern lighting system like this does not seem very complex in terms of the task at hand. However, it is still necessary to ensure a smooth implementation. However, also in this respect, the Andreas Tower literally stands out."



Image source: Markus Frutig, Inoveris,