Abstract: The invention is based on the problem of devising a circuit arrangement (10) for protecting electronic devices from incorrect logic voltages, wherein this circuit arrangement delivers increased protection against overvoltages, so that this circuit arrangement could also be used in multi-channel fail-safe systems that satisfy, for example, Performance Level “e” according to DIN EN ISO 13849. The circuit arrangement (10) has an input terminal (80) for connecting a power supply device and at least one voltage converter (90) that delivers, on the output side, an adjustable logic voltage. A controllable switching element (70) is connected between the one or more voltage converters (90, 95) and the input terminal (80). Furthermore, a first monitoring device (20) is provided for monitoring the logic voltage. The first monitoring device (20) is constructed so that it triggers the opening of the switching element (70) when the logic voltage reaches or exceeds a predetermined threshold.

Abstract: An arrangement for controlling a system includes a control and/or data transfer module (1) adapted to be snapped onto a mounting bar (2) and a plurality of I/O plug-in modules (3). Each I/O plug-in module (3) comprises a plurality of clip contacts (8) for connecting the system and a plurality of plug contacts (5) for plugging onto the control and/or data transfer module (1). In the plugged-on state an electrical connection is established between the I/O plug-in module (3) and the control and/or data transfer module (1). At least one I/O plug-in module comprises an electrical circuit element (11) disposed in the current path between at least one clip contact (8) and at least one plug contact (5). The arrangement for controlling a system enables adaptation of the installed automation solutions (1,3) in a highly flexible way to changes in system requirements in electrical cabinets with high packing densities.

Abstract: The invention is based on the problem of devising a circuit arrangement (10) for protecting electronic devices from incorrect logic voltages, wherein this circuit arrangement delivers increased protection against overvoltages, so that this circuit arrangement could also be used in multi-channel fail-safe systems that satisfy, for example, Performance Level “e” according to DIN EN ISO 13849. The circuit arrangement (10) has an input terminal (80) for connecting a power supply device and at least one voltage converter (90) that delivers, on the output side, an adjustable logic voltage. A controllable switching element (70) is connected between the one or more voltage converters (90, 95) and the input terminal (80). Furthermore, a first monitoring device (20) is provided for monitoring the logic voltage. The first monitoring device (20) is constructed so that it triggers the opening of the switching element (70) when the logic voltage reaches or exceeds a predetermined threshold.