Managing complexity: How Liebherr is simplifying the control of its MK cranes with Schlegel pushbuttons and switches

Numerous cab functions, one single control panel: this is how the tower crane specialist from Biberach combines the control for its fully electric mobile construction cranes into a very compact space.

Mobile construction cranes (Liebherr MK series, fully electric)

Customised operating unit with a central PCB and multi-pin connectors

Reduced wiring efforts, high robustness, scalable architecture

The challenge: lots of features, limited space

With around 1,500 employees, Liebherr-Werk Biberach GmbH is one of the world’s leading manufacturers of tower cranes. Its MK mobile construction cranes combine the advantages of a tower crane with the mobility of a truck-mounted crane – and, thanks to fully electric drives, are emission-free and quiet in urban use.

However, as performance increases, so does the complexity of operation. On cramped inner-city construction sites, the crane operator must be able to quickly identify functions and operate them safely – even under time pressure. What was required was an operating unit that

integrates standard cab functions such as lighting and generator control,
controls three windscreen wipers, including the cleaning function, interval control and rain sensor,
houses a 20-watt audio amplifier unit for the cab microphone and external loudspeakers,
and accommodates all of this within a very confined space right next to the armrest.

The solution: a central PCB instead of individual wiring

Schlegel developed a control panel tailored exactly to the spatial conditions of the crane cab: :

Bundled functions: A central PCB integrates the cab functions and keeps the system architecture clear and organised.
Simple connection: Multi-pin connectors reduce the wiring effort and simplify installation and servicing.
Early partnership: Schlegel was involved right from the prototype phase – design, electronic and practical requirements were coordinated in parallel.

The result: robust enough for everyday use on construction sites, scalable for the future

Practical: The operating unit is resistant to vibration, temperature fluctuations and continuous mechanical stress.
Ergonomic: Clearly structured control elements reduce the error rate – particularly during long long shifts.
Future-proof: The combination of minimal hardware requirements and bus-compatible architecture creates an expandable, easy-to-maintain platform.

Would you like to achieve similar results?

"“A reliable, collaborative relationship and direct on-site support enabled us to find fast and practical solutions.” “The robustness, reliability and quality of our machines are our top priorities. The Schlegel operating unit meets these requirements.”"

Development Team, Liebherr-Werk Biberach GmbH