Ulm Minster in Germany has the highest steeple in the world at 161.53 metres, and an interior of similarly vast dimensions. for this grand setting, Ingenieure Bamberger GmbH has developed a new lighting solution that is outstandingly precise and effective.
How exactly should a building be illuminated when electric light did not even exist back when it was originally built? How can respect for the historic essence and ancient master builders be accorded on the one hand, and high contemporary functionality be achieved on the other? These were among the questions facing Bamberger when the planning consultants came to develop a new lighting concept for Ulm Minster in Germany.
The designers, with specialist expertise in church lighting, responded to these challenges with specially designed luminaires which remain discreetly in the background and allow the magnificent architecture to take centre stage; LED Drivers from Tridonic are an important element of this sophisticated solution. On the one hand, they allow for large distances between control gear elements and LED light sources, and therefore a slim luminaire design. On the other hand, they ensure efficient operation of the luminaires and enable them to be controlled with many variants.
In keeping with the Minster’s Gothic architecture, vertically-suspended 3.2m long tubes stretching skywards each hold 20 to 24 LED lighting heads. Each head is individually aligned according to its task and provided with the corresponding optics; some emit light downwards on to the church pews and the ground, while others skilfully place the architecture in the spotlight way up to the vault.
“The clerestory provides the nave with daylight. This light allows onlookers to grasp the vast dimensions of the area and creates a formidable sense of space. We wanted to reinforce this effect with the artificial lighting, too,” explains Walter Bamberger.
The pendant luminaires provide the entire lighting solution for the nave and the aisles. They were placed inconspicuously in the pointed arches between the nave and aisle; so the lines of sight along the aisle remain free and the view into the vault is unobstructed.
This minimalist design could only be achieved thanks to the spatial separation of LED light sources and LED Drivers. Bamberger contacted Tridonic to supply the control gear elements for the LED luminaires, which were made by Metallbau Böhm; the ideal solution was the dimmable constant-current LED Drivers from Tridonic’s PREMIUM series. A total of 360 LED Drivers supply and control the 500 or so LED lighting heads.
The PREMIUM Driver has an adjustable output current between 900 mA and 1,800 mA to offer flexibility during connection of the LED lighting heads. The configuration was such that only SELV voltage is present at the luminaires and no additional protection against accidental contact is therefore required.
In Ulm Minster, the DALI protocol is used by the various integrated interfaces. Almost all of the LED lighting heads are dimmable and switchable. This enables various light scenarios to meet the requirements of every occasion.
The high-quality electronics along with the fact that the Drivers work with amplitude dimming rather than pulse width modulation (PWM) are further advantages. As a result, the control gear elements can be located at a distance from the luminaires in a collective housing under the roof of an aisle. Thanks to amplitude dimming, no problems with electromagnetic compatibility (EMC) arise; LED dimming using PWM would have proven problematic due to the distances between drivers and LED modules.
Tridonic verified the fact that the installation met all EMC requirements using measurements in its own laboratory. Such services are provided for luminaire manufacturers, lighting planners and other customers as part of the so-called design-in process. For this purpose, Tridonic tests the technology to ensure it operates safely and in compliance with regulations including under non-standard operating conditions.
The modern LED Drivers provide further benefits. They work at an extremely high efficiency of 91 % and a power consumption in stand-by of less than 0.15 W. The devices integrate numerous protective functions, for example against overtemperature, short circuit and overload, with a nominal service life of up to 100,000 hours. Tridonic offers a five-year warranty.