In example implementations, a powder level sensor is provided. The powder level sensor includes a capacitive sensor, a processor, and a cleaning mechanism. The processor is communicatively coupled to the capacitive sensor. The processor interprets a measurement of the capacitive sensor to detect a layer of residual build material on a surface of the powder level sensor. The cleaning mechanism may be communicatively coupled to the processor. The processor activates the cleaning mechanism to remove the layer of residual build material on the surface of the powder level sensor.

A dispensing system for a beverage comprises in a tap system a bore for housing a duct. Along the bore, close to or on the duct, at least two electrodes are provided such that at least at some locations along the duct, the two electrodes are provided opposite to one another with the duct in between, thus constituting a capacitor. An oscillating signal is provided to one electrode and a signal is read out from the other electrode. As a beverage is drawn through the duct in a container, capacitance of the capacitor changes. The flowing beverage may have different characteristics, but capacitance may also change as the beverage in the duct is in conducting contact with a container that may be in contact with a ground contact. The change of capacitance results in a change of the amplitude of a detection circuit connected to the second electrode.

The invention relates to devices for detecting the fill level of media in containers. The devices are distinguished, in particular, by a simple and reliable detection of the fill level. For this purpose, multiple measuring points, each consisting of a series circuit of a resistor and a p-n junction, are spaced apart from one another. Each measuring point is connected, on the one hand, to an input of a multiplexer. On the other hand, the measuring points are connected to a reference potential. The output of the multiplexer is connected to a control device, wherein the control device is a control device periodically supplying a voltage to the measuring point connected to the control device via the multiplexer and measuring the voltage drop, a control device determining the medium from the temperature-dependent forward voltages resulting from the different thermal properties of the medium and a control device ascertaining the fill level from the consecutive measuring points.

A level sensing controller includes a signal generator circuit to generate an excitation signal. The controller also includes a connection to route an inverse of the excitation signal to a first polar electrode of a first capacitor. The first polar electrode is coupled to a container to hold liquid. The controller also includes a connection to route the excitation signal to a second polar electrode of a second capacitor. The second positive polar electrode is coupled to the container. The controller also includes a connection to a sense electrode to form the first capacitor with the first polar electrode and to form the second capacitor with the second polar electrode. The controller also includes a measurement circuit configured to measure charge at sensing electrode and determine, based on the measured charge, whether a liquid in the container has reached a level of the second polar electrode.

The proposed technical solution relates to measuring technology and is intended for measuring levels of measured medium in various branches of industry. The technical problem solved by the claimed invention is the production of a capacitive level sensor which demonstrates high operational reliability and provides highly accurate measurements. The technical result achieved by using the claimed invention consists in overcoming the disadvantages of the prior art, increasing the reliability and manufacturability of the design and thus increasing the accuracy of interface level measurements.

A capacitive level sensor device, for detecting the level of a medium contained in a container, comprises a circuit support, which extends longitudinally substantially according to level-detection axis. The circuit support has, in a detection region thereof, at least one first plurality of first capacitive elements, which comprise at least one first array of first electrodes (J), preferably spaced from one another along the level-detection axis, which are arranged in a position corresponding to at least one first side of the circuit support. The sensor device has a casing body which comprises an electrically insulating and fluid-tight detection portion, which covers the detection region of the circuit support. The detection portion of the casing body comprises an overmoulded outer coating, made of a first electrically insulating polymeric material, which defines an outer surface of the casing body designed to be in contact with the medium the level of which has to be detected. The first electrodes (J) are enclosed within the supporting structure of the circuit support at least at the detection region thereof, and, at least at the detection region, between the overmoulded outer coating and the supporting structure of the circuit support there is set at least one intermediate layer made of an electrically insulating material different from the first material.

One or more examples relate to a detector. A signal that the detector is configured to sense is a differential value. Such a differential value may be indicative of a difference in self-capacitance indications that are exhibited at first and second internal capacitors. Such a differential value may be proportional to a relationship between a first material and a second material present at a device-under-test coupled to electrodes of the detector. Such a differential value may be proportional to a vertical elevation of a surface of a material present at a device-under-test coupled to electrodes of the detector. A difference in coupling capacitances may be obtained by performing complimentary acquisition processes utilizing symmetric capacitive sensors. When the acquisition processes are performed substantially simultaneously, coupling error indications that may be present in the self-capacitance indications are not present in the differential value.

The invention is an impedance sensor with: a probe which can be influenced in a capacity by a medium surrounding the probe, a measuring oscillation circuit in which the probe is arranged as a capacity-determining element, an electronics unit with a signal generator for excitation of the measuring oscillation circuit and a signal detector for determining a response signal of the measurement oscillation circuit and a signal processing unit connected with the electronics unit, wherein the signal generator is designed as a digital controllable circuit.

Devices and corresponding methods for capacitive foam detection in liquid containers are disclosed. The device has a sensor with a measurement electrode having a plurality of sub-electrodes, a bottom plate that is used as a counter electrode for arranging a liquid container, a sensor electronic unit that is connected to the measurement electrode and the bottom plate and is adapted to determine an impedance, in particular a capacitance, between the measurement electrode and the bottom plate, and an evaluation unit, the measurement electrode being arranged substantially perpendicularly to the bottom plate.

A fluid property sensor may comprising an integrated circuit (IC) including a fluid level sensor, and/or a pressure sensor; and an external interface electrically coupled to a proximal end of the EC, wherein the pressure sensor may be configured to measure a flexure of the fluid property sensor.