Case study: Multimedia fountain with LED lighting

June 22, 2009
Lediko has delivered LED RGB modules for one of the world’s largest multimedia fountains, writes Adam Wilanowski.
Since June 4, 2009, inhabitants and tourists visiting Wroclaw, the capital of Lower Silesia, situated in the southwest of Poland, are able to admire one of the greatest multimedia fountains in the world illuminated with high-power LEDs.

The fountain is located in a very attractive tourist area of Wroclaw, next to the Centennial Hall, listed as a UNESCO World Heritage Site. The Centennial Hall is a part of a larger historic architectural complex. Additionally, in the close vicinity of the hall there is a beautiful park, an extensive Wroclaw Zoo, and an admirable Japanese Garden. The modern multimedia fountain has replaced the former fountain and was inspired by the original vision of the architects from the beginning of the 20th century.

The contractor of the fountain's renovation - the Gutkowski company which specialises in the construction of modern fountains, swimming pools and reservoirs, entrusted the design and production of the LED RGB modules to Lediko. In order to create spectacular illuminations the companies decided to use XLamp LEDs produced by Cree and highly efficient lenses produced by Ledil.

The fountain is illuminated by nearly 800 of different sizes lighting points installed under water. In the trough of the fountain of the area of 10000m2 (107639ft2) there are about 300 water nozzles of different kinds. The range of water devices is very wide: foaming, dynamic, hazing, point and palm nozzles as well as geysers. Water columns rise up to 40 meters.

Multimedia animations displayed by classic and laser projectors can be admired on a 700m2 (7535ft2) water screen. The fountain is additionally equipped with 3 unique fire nozzles. The whole spectacle is supplemented with music.

Lediko was responsible for delivering modules consisting of 16 and 12 high-power LEDs for 400 lighting points. Altogether the modules consist of over 6500 XLamp LEDs. Lediko have been specialists in this field since the beginning of 2005. In this project Lediko adapted to the needs of the application, using the knowledge and skills of the company in the construction of reliable LED modules confirmed by the status of Cree LED Solution Provider.

Technical advantages

High-power LEDs are characterised with advantages especially important in applications like the multimedia fountain. One of them is low power consumption in comparison to halogen lights with coloured filters. XR-E series high-power LEDs (blue, green) and XR-C (red) used in the installation are supplied with the current up to 700mA. The modules consume up to 35W when all RGB channels are driven with maximum current.

Nearly 400 LED fixtures which base on the modules delivered by Lediko altogether consume about 14 kW. The Lediko engineers assess the power consumption of a corresponding installation basing on halogen sources of light with colored filters at about 10 times higher.

Extremely important features taken into consideration while choosing high-power LEDs for the basic source of the multimedia fountain illumination were: very long lifetime, reliability and resistance to vibrations. The prestige of the fountain in combination with the high cost of maintenance requires the high quality of the source of light in order to meet the expectations of the public and guarantee unforgettable impressions. What is more, the lighting system has to be failure free for thousands of hours.

Unquestionable advantage of applying LEDs in the multimedia fountain is the simplicity and flexibility of control and the safety of supply. Due to the short time of switching on and off, LEDs are ideal for dynamic shows. The quick reaction of LEDs is a guarantee of amazing, colourful visual impressions through mixing basic RGB colours, which in combination with music and water nozzles creates a fascinating multimedia show.

The LED modules are connected to drivers controlled with DMX signal and supplied with constant voltage lower than 20V, which corresponds to the European Union norms for supplying devices working in water.

The next essential feature of LEDs is the fact that they are very small point-sources of light, which enables the use of small but effective optics with strong concentration of light and, consequently, the construction of considerably small lighting fixtures. Due to the high intensity of the emitted light water columns are illuminated up to 40 meters and the small fixtures can be installed just next to the fountain nozzles. These two parameters – the size and the intensity of the source of light – are responsible for the quality of the lighting effects obtained during the spectacular shows of the fountain.

The LED module designed and produced by Lediko guarantees proper cooling of the LEDs. The company decided to choose a solution basing on double-sided FR4 substrates with a technology of thermal holes because of the need of mounting through-hole elements on the module (connectors adapted to thick supplying wires of diameter 2.5mm2). When the fixture not immersed in water, at room temperature is supplied with maximum power, the temperature of the heat sink of the fixture does not exceed 50°C. There is a thermal protection mounted on the LED module which reduces the LEDs current. The multimedia fountain requires highly infallible LED modules and thus the fountain's constructors cannot rely only on high quality diodes. Additionally, the LEDs have protection against exceedingly high supply current, protection against electrostatic discharge (ESD) and protection against wrong polarisation.

Summary

The multimedia fountain successfully created by the Gutkowski company in cooperation with Lediko, a member of Cree LED Solution Provider network, is an irrefutable proof that such networks of customer support are helpful and reasonable. In strictly defined, advanced undertakings requiring vast experience and thorough knowledge of various fields, cooperation between professionals enables breaking the barriers of design and lighting to achieve a new level of quality. In this case it is the breathtaking multimedia fountain, but it as well might be a different, advanced application using the advantages of high-power LED modules as well as experience and skills of the designers and constructors.