The Traumpalast in Leonberg is a real jewel and attracts cinema lovers from a large region. When constructing their latest movie theater, the Lochmann Filmtheaterbetriebe in Rudersberg designed everything to ensure that their visitors would have a cinema experience “par excellence”. Visitors can relax in their comfortable seats with plenty of leg room, watch movies in modern 3D technology in all ten cinemas, and treat their ears to a very special sound experience.
One fascinating highlight for all visitors is the impressive light show. “Different lighting moods are an integral part of the cinema experience at Lochmann movie theaters,” says Eduard Henke, CEO of the Freilicht! company from Berlin, which installed the extraordinary decorative lighting in the Traumpalast. Already upon approach to the Traumpalast, the colorful lights on the façade cast their spell on the visitors. The luminous steps in the lobby are a real eye-catcher. Eduard Henke and his employees also installed countless LEDs in the cinema auditoriums. They highlight edges and base boards. Before a movie starts, a colorful light show raises visitors’ anticipation of the latest blockbuster.
Freilicht! installed 3500 meters of LED strips in the new Traumpalast in Leonberg. Eduard Henke commissions the production of these strips with RGB LEDs specifically for his requirements. The active combination of red, green, and blue light covers the entire color spectrum. The LEDs are controlled by dimmers located in standardized control cabinets. The dimmers pass the three pulse-width-modulated voltages to the LEDs to produce the desired colors and level of brightness.
Since the cinema lighting requires a lot of power due to the sheer volume—despite the very efficient LED technology in itself—and intensive use over many hours a day requires a sustained, high-powered installation solution, Freilicht! decided to implement the supply of power with the 24-VDC Emparro 3~ switching power supplies from Murrelektronik. Roughly 80 components of this highly-efficient power supply are installed in the control cabinets of the Traumpalast and ensure a reliable supply of power.
The decision for a three-phase power supply was due to the special characteristics of cinema operation: The balanced three-phase load means that the neutral wire is not a current-carrying conductor. This prevents any negative effects on the sound system, with its excellent Dolby-Atmos technology.
Freilicht! CEO Eduard Henke was impressed by the high efficiency of the Emparro power supplies of up to 95%: “This means that they produce very little heat and do not need a cooling system in the cabinet,” the expert explains. The components experience little thermal load and last longer. Since the Emparro power supplies by Murrelektronik also set a standard in terms of the component width and output the same power at half the width (compared to many other devices), Freilicht! is able to use smaller control cabinets. This is a great benefit since they are installed in the projection booths of the individual auditoriums where space is scarce.
The Freilicht! employees have set the utilization level of the devices at about 70% of the load limit. “This will give us maximum life expectancy and high reliability. We wouldn't want our visitors to end up sitting in the dark,” says Eduard Henke. The fact that switching to full lighting after the light shows results in brief peak loads is not a problem: The Power Boost function (150% power for up to 5 seconds) and the Hyper Boost function (approximately 400% for up to 20 milliseconds) ensure that Freilicht! need not lose any sleep over this.
It is interesting that Freilicht! uses an operating voltage of 24 V to supply the LED strips. Eduard Henke explains: “This is actually an innovation. Usually people use 12 V.” He refers to Ohm’s law which states that for the same power, twice the voltage results in only half the current. “Accordingly, we have a proportionally lower voltage drop and this means that the LEDs at the end of the auditorium are as bright as the one’s at the front.”
As Freilicht! manages several cinemas in different locations in Berlin, remote maintenance is an exciting topic to them. For instance, a status report on the PWM modules is sent to the control center every week. One highlight of the Emparro power supplies that goes even further is the preventative diagnostic function. The device monitors diverse parameters including internal temperature, load situation during operation, the number of start processes, and the life span of the components. Once the optimal time for replacing the Emparro 3~ 40 A has been reached, this information is passed on to the control center via an easily integrated signal contact. The power supply is not replaced too early, which ensures optimal use of available resources, but also not too late, which avoids failures and annoyance.
Manuel Senk, product manager at Murrelektronik and cinema buff, says: “The Traumpalast sets some impressive standards. We are proud to have contributed to the efficient supply of the lighting technology, and as a movie buff it makes my heart beat faster.”