An impedance limit switch is configured to determine a limit level of a medium. The switch may include a measuring probe having an oscillator circuit; and an electronic circuit configured to generate an excitation signal for the oscillator circuit. The electronic circuit is further configured to sweep a frequency of the excitation signal and determine a resonance curve of the oscillator circuit. The electronic circuit is further configured to adapt an amplitude of the excitation signal dependent upon the resonance curve in order to reduce an EMC radiation of the switch.

A device, for capacitive measurement of a height of a fluid in a tank, comprises at least one pair of capacitors extending in a longitudinal direction. A first capacitor forms first geometric patterns defining a first line capacitance. A second capacitor is opposite the first capacitor and forms second geometric patterns defining a second line capacitance. The first and second geometric patterns are arranged so that the first and second line capacitances, integrated in the longitudinal direction, have a sum that depends on the position of the fluid in the longitudinal direction. The first and second line capacitances, integrated in the longitudinal direction, have a difference that is a constant for reference positions of the fluid in the longitudinal direction.

An angle detection device for a fuel fill level detection device, including: a support, a potting composition, which is arranged on the support in coherently bonded manner; a sensor for the contactless detection of an orientation of a magnetic field of a magnet, which is at least partly arranged in the potting composition, in particular on the support, and at least one conductor track which is arranged flat on the support, in particular in coherently bonded manner.

An analyzer for a grease interceptor for measuring levels of fat, oils, and grease (FOG), water, sludge and air having a probe which includes a controller and a sensor sub-unit. Sensor circuits include a microcontroller, timers, and sampling capacitors. The sensor sub-unit includes a plurality of electrode ring pairs coupled to a plurality of timers for converting capacitance measurements to frequencies under the control of a microprocessor in the controller. The frequencies identify the measured levels.

A physical quantity detection device including a container that is formed with an accommodation space accommodating a detection object formed of a dielectric, a first electrode and at least one second electrode that face with each other via the accommodation space, and an electrostatic capacitance detector that detects an electrostatic capacitance between the first electrode and the second electrode by applying an alternating current voltage between the first electrode and the second electrode. A frequency of the alternating current voltage applied between the first electrode and the second electrode is 1 kHz or higher.

Disclosed in one embodiment are a device for measuring water level by using a capacitive technique, and a method therefor. A device for measuring water level comprises: an electrode unit which includes a first electrode and a second electrode arranged in parallel in a lengthwise direction, and which allow voltages to be applied to the first electrode and the second electrode; and a control unit for measuring the applied voltages, calculating the amount of reference charging time it takes to reach a second voltage from a predetermined first voltage on the basis of the measured voltages, and determining water level on the basis of the calculated reference charging time.

A system for power and data communications within a fuel tank and across a wall of the fuel tank includes a fuel height sensor and a sealed connector extending through a wall of a fuel tank. The system also includes an electric power connection between the fuel height sensor and the sealed connector. The system additionally includes an internal data communications connection between the fuel height sensor and the sealed connector, wherein the electric power connection comprises a resistive non-metallic wire.

A fuel gaging system, such as may be used in determining an amount of fuel in an aircraft fuel system, includes a capacitance probe and a capacitance measurement circuit component including high resistance elements. The capacitance measurement circuit component includes a first excitation generator, an excitation wire connected between the first excitation generator and the capacitance probe, and a signal wire connected to the capacitance probe with the capacitance probe being connected between the excitation wire and the signal wire, wherein the first excitation generator generates an input signal applied to the excitation wire and an output signal is read from the signal wire to determine a capacitance at the capacitance probe. The system further includes a wire resistance measurement circuit component configured to isolate a contamination resistance to account for variations in wire resistance of the system wires in determining the capacitance at the capacitance probe; and a contamination compensation circuit component configured to compensate for fuel contamination in determining the capacitance at the capacitance probe by compensating for a slope error in the output signal.

A sensor device for detecting liquid, in particular in a controller of a steering system of a vehicle, includes at least one sensor element and a testing unit. The sensor element is electrically connected to the testing unit. The testing unit has a signal transmitter, connected to the sensor element, that is configured to generate an electrical test signal, and a signal receiver, connected to the sensor element, that is configured to detect a reaction signal for the electrical test signal. The signal transmitter and the signal receiver are each connected at high impedance to the at least one sensor element. The testing unit is configured to detect the reaction signal at least at a time as a first reaction signal for which the electrical test signal has been generated in order to infer a presence of the medium.

A device for manual application of a liquid. The device may be used for painting, marking, drawing, writing and/or applying make-up to keratinous surfaces. The device includes a capillary store for the liquid, the capillary store having a filing level, and a measuring device for measuring the filing level of the capillary store.