A modular operating concept from Schlegel consists of a bus-specific base module, which can be expanded with up to 15 bus-independent I/O expansion modules. It is designed to enable the flexible and low-wired equipping of control panels or machine systems. Each of these modules is equipped with eight illuminated contact sensors. In total, up to 128 control points with 128 indicator lights can be integrated. The modular operating concept is available for the bus systems AS-Interface, CANopen, Profibus, EtherCAT, Profinet I/O and Ethernet IP. Schlegel offers the standardized modules in a fixed grid of 25 x 25 mm / 27 x 27 mm / 30 x 30 mm. The individual modules can be arranged in a grid. Thanks to a plug-in principle, no additional spacer bolts need to be fitted in the front panel to secure the modules. The base module is supplied with a +24 V DC supply voltage and the bus signal.