A system for controlling a magnetic switch in urinals includes a switch control unit and a control signal receiving unit connected to the switch control unit via a magnetic field. The switch control unit is configured to generate and eliminate the magnetic field based on a received pulse signal. The control signal receiving unit outputs an on signal in response to sensing the generation of the magnetic field and outputs an off signal in response to sensing the elimination of the magnetic field.

A method for measuring a physical quantity with a, particularly inductive, sensor element and for providing a sensor output depending on the physical quantity. The sensor element is part of a resonant circuit whose attenuation depends on the physical quantity being measured. The resonant circuit is excited to generate a periodic oscillation signal, the amplitude of which depends on the attenuation. The oscillation signal is compared with a comparator threshold value in a comparator to produce a periodic comparator signal with a duty cycle depending on the comparator threshold value. The comparator threshold value is set to be different from a mean value of the oscillation signal so that a duty cycle different from 50% is achieved. The sensor output is output depending on the duty cycle of the comparator signal.

A magnetic switch includes a magnetic field sensing system configured for performing a measurement of the component of the magnetic field in at least two different directions and providing a signal representative of the measurement. A comparator allow to sequentially compare the signal with a respective threshold value. The comparator are adapted to provide a first threshold value being a predetermined value for a first comparison wherein the switch is configured to repeat the comparison using the signal representative of the measurement in a different direction and a respective threshold value. The comparator are further adapted to provide a further threshold value for the further comparison. The threshold value is chosen in accordance with at least one measurement of the component of the magnetic field used in a previous comparison. The magnetic switch also comprises a connection to output the result of at least one comparison.

An inductive proximity sensor and a method for the detection of an object having at least one coil, wherein at least one transmitted current pulse can be applied to the coil by a control and evaluation unit and the control and evaluation unit is configured to output an object determination signal, wherein the control and evaluation unit is configured to scan at least one induced voltage pulse that has been generated by the transmitted current pulse at the coil in a plurality of sections from or after the time of the application of the transmitted current pulse and to form scan values, whereby the voltage pulse is digitized, wherein the control and evaluation unit is configured to evaluate the scan values for an object detection of a metallic object, wherein the control and evaluation unit is configured to scan the transmitted current pulse that has been generated at the coil in at least two sections from or after the time of the application of the transmitted current pulse and to form transmitted current scan values, wherein the control and evaluation unit is configured to determine a rise in the current increase of the transmitted current pulse from the transmitted current scan values, and the control and evaluation unit is configured to end the transmitted current pulse in dependence on the detected increase of the transmitted current pulse.