The TwinCAT Building Automation software and the "eXtendable Room Box" together represent an integrated system that reduces engineering time for building automation solutions. TwinCAT Building Automation enables simple configuration of control functions and the automated composition of hardware modules in a single tool. The flexible and extendable "eXtendable Room Box" (XRB) from Beckhoff includes the freely selectable mounting box and the necessary Bus Terminal I/O. The user obtains, virtually by mouse-click, a fully configured box that can be wired in the building via plug-and-play. For technical planners and system integrators, this ensures minimal engineering costs coupled with the greatest possible freedom in design: maximum customisation of the completely prefabricated boxes is possible down to a quantity of one.