To ensure the suitcase arrives safely!

Behind the scenes of Germany's most important airport, one of the world's largest baggage handling systems operates reliably. The current expansion of this system, with clockwork precision, is facilitated by the new intelligent power monitoring device in miniature format - the LOCC-Box-M.

At Frankfurt Airport, a third terminal is currently under construction. Three concourses with dozens of gates are connected to the new, light-filled main building. While a new driverless Skyline train connects Terminals 1 and 2, the baggage handling system (BHS) of these terminals is connected via a 1.6-kilometer-long tunnel.

The actual domain of the system lies in mezzanine levels and basements of the enormous buildings. Each day, around 50,000 pieces of luggage sprint at a speed of 18 km/h on a total of 81 kilometers of tracks, ranking it at the forefront in terms of size and performance. The fully automated system is powered by a multitude of drives and switches, resembling a major train station and operating precisely like clockwork. Each piece of luggage travels gently in a blue transport tray. In addition to human packers, even robotic arms assist in the transfer process.

The extensive system is monitored around the clock and maintained during operation by Fraport, the airport operator. For this purpose, 40 maintenance personnel are on duty per shift. Sometimes it's a overheated drive motor causing an issue, other times it's just a loose connector or a detached luggage tag sticker that confuses a sensor.

Standstill is the system's greatest enemy, and ensuring maximum operational safety is the top priority. This also applies to current control. One core task is circuit protection in the event of a short circuit. The new baggage handling system (BHS) of Terminal 3, relies on a proven and reliable solution from LÜTZE for electronic 24V load monitoring: the LOCC-Box, now available in a new mini format. As a result, Fraport becomes one of the first customers to adopt this smallest and most compact load monitoring solution with 40 adjustable settings on the market.

In many control cabinets worldwide, the LOCC-Box (Lütze Overload Current Control) is virtually a standard when it comes to intelligent monitoring of short circuits and overloads. Thanks to its patented analog tripping behavior along five defined characteristics – from fast (for sensors, for example) to super slow (for motors or fans) – selective power supplies can be established. Only the affected circuits are switched off, allowing all others to continue running smoothly, thus keeping the entire system operational.  The system indicates detected faults through green and red LEDs; diagnosis can be conducted through the device itself or via appropriate interfaces to various fieldbus systems such as Profinet or EtherCat.

Why did they opt for the new mini variant?

To gain insights into this decision, SEAP Automation, the company responsible for the control technology in the construction of Terminal 3, was consulted. The company has been collaborating with Frankfurt Airport in baggage handling for over 30 years and plays a significant role in ensuring the smooth operation as described earlier.

The decisive factors for the LOCC-Box-M are its slimmer and smaller construction (installation depth of 86 mm, height of 92 mm, construction width of 8.1 mm), as well as the up to 40 possible sealable settings. It is employed in almost every control cabinet across the system, totaling over a thousand units.  "We definitely consider the LOCC-Box to be the most reliable product in the market when it comes to safe short-circuit shutdown, even for long cable lengths or small cross-sections," explains Anton Pajonk, Managing Director of SEAP AUTOMATION GmbH. This applies to the super-compact mini variant as well, which also offers the five patented characteristics and the analog tripping behavior.

There's more LÜTZE technology powering the baggage turbo of Terminal 3: in addition to electronic fuses, compact power supplies are also part of the equation. This package of 24V power supply is positioned on the AirSTREAM wiring system or its compact version. In fact, LÜTZE has a strong presence at Germany's primary hub: if you include the previous version of the current wiring system, Fraport has been relying on channel-free wiring and its climatic and spatial advantages for decades. Various switches, sockets, and motor cables are also in use along the many kilometers of baggage handling system tracks.

The LÜTZE engineers managed to reduce the size of the previous current monitor, while retaining all the essential functions. Only a few connection parameters have been adjusted to fit the mini format. Only a few connection parameters have been adjusted to fit the mini format.

Author: Martin Baum, sales project manager, Friedrich Lütze GmbH