EP1565735A1 - Procede et dispositif pour determiner la teneur en eau et la conductivite dans des sols et dans des produits en vrac - Google Patents

Procede et dispositif pour determiner la teneur en eau et la conductivite dans des sols et dans des produits en vrac

Info

Publication number
EP1565735A1
EP1565735A1 EP03772275A EP03772275A EP1565735A1 EP 1565735 A1 EP1565735 A1 EP 1565735A1 EP 03772275 A EP03772275 A EP 03772275A EP 03772275 A EP03772275 A EP 03772275A EP 1565735 A1 EP1565735 A1 EP 1565735A1
Authority
EP
European Patent Office
Prior art keywords
voltage
conductivity
sensor
charging
water content
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP03772275A
Other languages
German (de)
English (en)
Inventor
Ruth Bernhard
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Helmholtz Zentrum Muenchen Deutsches F
Original Assignee
Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt GmbH filed Critical Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt GmbH
Publication of EP1565735A1 publication Critical patent/EP1565735A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/22—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance
    • G01N27/223—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating capacitance for determining moisture content, e.g. humidity
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/24—Earth materials
    • G01N33/246—Earth materials for water content

Definitions

  • the invention relates to a method and a device for determining the water content and conductivity in soils and bulk materials according to the first and sixth claims.
  • the dielectric constant ⁇ m between two electrodes serves as a reliable measure of the water content in a bed or a soil sample.
  • Water itself has a very high dielectric constant compared to many other materials, so that even a low level of moisture in the measurement volume, ie in the soil sample or in the bed, leads to a significant change of ⁇ m .
  • Typical areas of application for such moisture determinations can be found particularly in the monitoring of soils and in the quality control of agricultural cereal products (e.g. for flour, legumes, soybeans), but also in general in the production and conveying technology of moisture-sensitive goods (e.g. sugar ).
  • the electrical conductivity of a moist material can be used as a measure of contamination, which has a significant influence on the electrical resistance of the moist material.
  • a parallel measurement of the dielectric constant ⁇ m and the conductivity of a bed or a soil segment is suitable not only for the determination of the water content but also of the contamination dissolved in the water.
  • the following methods for the simultaneous determination of a dielectric constant ⁇ m and a conductivity ⁇ m in materials are known for the characterization of soils and bulk materials:
  • TDR probe differences in transit time along a waveguide
  • the pulse runs along in a waveguide, a second waveguide serves as a reference mass.
  • the dielectric constant is calculated from a measured pulse speed in the TDR probe and then, for example, the water content ⁇ of a material is determined.
  • An increase in the dielectric constant leads to a decrease in the pulse speed.
  • the relationship between ⁇ m and ⁇ must be assumed to be known.
  • a cable tester is required, which must have a bandwidth of a few 4 GHz to over 100 GHz depending on the time resolution required.
  • [2] also describes the determination of the conductivity ⁇ m of a material using the TDR method from the damping of the impulse.
  • [3] proposes a capacitance method using an electromagnetic resonant circuit to determine the dielectric constant ⁇ m of the material, which can be implemented much more economically than the TDR method .
  • a sensor is designed as a capacitor with two capacitor electrodes connected to an oscillator.
  • An oscillator an analog electronic circuit, generates a sinusoidal output signal, the frequency f OSz of which is determined by the capacitance of the sensor C s , but also by other components. elements, in particular the necessary inductance L for the oscillator, is determined.
  • the connection is
  • a frequency can be recorded precisely, reliably and inexpensively using simple means.
  • exact determinations of dielectric constants are also possible with this method.
  • the frequency f osz generally has a dependency on the conductivity of the material examined, an increasing conductivity generally leading to lower frequencies. A higher dielectric constant is exchanged in this way. However, this influence of the conductivity decreases with increasing frequency, whereby one preferably measures with high frequencies to determine the dielectric constant. Even if the influence of conductivity is reduced, it is still retained.
  • Conductivity ⁇ m of a material the sensor can therefore be regarded as a complex resistance in an equivalent circuit diagram.
  • a network analyzer is again required to determine the complex resistance with a real and an imaginary component, which increases the effort for a simultaneous detection of the water content and the conductivity accordingly.
  • the object of the present invention is therefore to provide a further method and a device for carrying out a method for determining the water content and the conductivity in soil and debris, which is also characterized by less effort.
  • the object is achieved by a method and a device according to the features of the first and sixth patent claims. Preferred embodiments of the invention are the subject of the dependent claims.
  • the invention relates to a method for determining the water content and conductivity in soils and bulk materials.
  • the method initially involves placing a capacitive sensor in the ground or in the bulk material.
  • the sensor is then charged with an external constant current source, an initial current being adjustable and thus predeterminable.
  • the capacitive sensor is charged from a predeterminable first voltage threshold value to a predeterminable second voltage threshold value, with either the voltage curve over time being recorded as continuously as possible and recorded as a voltage-time diagram, or the charging time required for this being measured between the two voltage threshold values.
  • a second charging process of the sensor with the constant external voltage supply is required to determine a second charging time, for which purpose either the initial current and / or at least one of the two voltage threshold values has to be changed , The determination of the water content and the conductivity by verifying the two charging times or the voltage-time diagram.
  • the verification is carried out by comparing the recorded voltage curve profile with the solution of a corresponding linear system of differential equations.
  • the period of the measurement signal is composed of the charging and discharging time of the sensor.
  • the period of the measurement signal is generated from the charging and discharging time of the sensor, the charging time having known discharging behavior being determined in a particularly advantageous manner with the aid of a simple and exact frequency measurement of the periodic loading and unloading.
  • the two frequencies of the two periodic measurement signals are also used to determine the water content and the conductivity.
  • a storage oscilloscope, a transient recorder or a fast measurement data acquisition card, which forwards the acquired data to a process computer or a PC for further evaluation, is ideal for voltage-time diagrams, the periodic measurement signals or the charging times.
  • Fig. 1 is an equivalent circuit diagram of the sensor in its basic form
  • Fig. 3 shows the equivalent circuit diagram of the sensor with insulated electrodes in the presence of a high conductivity of the dielectric.
  • Fig. 8 several charging curves and an upper voltage threshold T in a voltage-time diagram.
  • Fig. 1 shows the equivalent circuit diagram of the sensor in a floor segment or a bed.
  • the conductivity ⁇ m of a material can be represented by an ohmic resistance R s , which is connected in parallel to C s .
  • R s and ⁇ m have the relationship
  • G is a constant geometry factor of the sensor, which can be determined by a calibration measurement.
  • the electrical conductivity in water is also not a metallic conductivity with displaceable charges and an opposite charge on the stationary phase, but an ionic conductivity. This means that in this case the applied electric field separates the charges due to the existing conductivity and pulls them further apart, so that a dipole is induced. The dipoles drift apart. follows until the resulting electric field of the separated ions compensates for the external field.
  • ⁇ ion g ( ⁇ m ) (5).
  • ⁇ must be determined as the material constant for a soil to be examined or for a bed. ⁇ links the two sizes eats R s and Ci on , so that in addition to C s, only one additional quantity has to be determined, namely R s .
  • the device 2 shows the basic structure of the device with a multi-vibrator circuit for determining the water content and the conductivity in a simplified circuit diagram.
  • the sensor 4 forms together with the load resistor R a 5 an RC element which essentially determines the time constant and thus the frequency of the circuit.
  • the multivibrator circuit essentially consists of an operational amplifier as an active element 9, which is connected on the one hand with its signal output 6 to the load resistor 5 and the part of the voltage divider (resistor 11), on the other hand the voltage 7 between sensor 4 and load resistor 5 and the voltage 8 between taps two further resistors 10 and 11 (voltage divider).
  • the time dependence of the charging curve (voltage 7) at the sensor 4 is determined by the capacitance value of the sensor, the resistor R 5 and a further specification of circuit and the sensor. If the voltage 7 at the sensor 4 reaches a certain threshold voltage U s ⁇ , then the active element 9 switches over and the sensor 4 is discharged. At this stage, the voltage 6 changes to another constant value U 2 . When a lower, ie second, threshold voltage U s2 is reached, the discharge is ended, the active element is switched over again and the sensor is recharged. The output signal 6 is thus a digital square wave signal. With a smaller sensor capacity, charging and discharging processes are faster and the output signal shows a higher frequency.
  • the dielectric constant ⁇ m of a material is first determined using the capacitance method with the aid of the multivibrator circuit, the sensor 4 having the capacitance C s being charged via a resistor R a 5 and discharged again at a specific voltage.
  • a periodically alternating charging and discharging results in a signal sequence with a frequency f, the time constant being determined by the RC element with R a and C s .
  • the occurring frequency f f h (R a , C s ) (7)
  • the capacitance of the RC element is thus influenced by the resistance, an increasing dielectric constant causing a decreasing frequency f.
  • a digital signal is generated directly, which is less susceptible to interference and in which the frequency can also be easily determined.
  • the circuit does not require an inductance L, which can also be disturbed from the outside.
  • the frequency f is also influenced in this case by the conductivity ⁇ m of the material.
  • the frequency f decreases as ⁇ m of the material increases.
  • the decisive point of this dependency is no longer the frequency as in the case of the oscillator, but the resistance R s , which is given by the conductivity of the material as above and which is parallel to the sensor capacitor C s 1 and which leads to C s is charged less, but the capacitor C 10n 3 is connected in series (FIG. 1).
  • Increasing the conductivity leads to a lower R s and also to a lower frequency. It is therefore not clear whether a lower frequency is due to an increase in the dielectric constant or an increase in the conductivity. A higher conductivity can therefore simulate a higher dielectric constant. Only if
  • the device according to FIG. 2 has to be modified.
  • the modifications relate to additional electrical circuits on the digital multivibrator circuit, with which various electrical properties Ei can be varied in a targeted manner.
  • the determination is carried out with measurements with different settings Ei on the same examination object, several frequencies fi being determined.
  • the properties of the material ⁇ m and ⁇ m can then be determined from these frequencies by calculation.
  • the sensor 4 corresponds to a parallel connection of the actual sensor capacitance C s 1 and the series connection of resistor R s 2 and the capacitor Ci ⁇ n 3, which is determined by the conductivity ⁇ m of the material.
  • These electrodes of sensor capacitance 1 must be insulated if the material has a high conductivity. This insulation acts in the equivalent circuit as a series connection of two further capacitors Ci 12 (see FIG. 3).
  • the first embodiment is shown in FIGS. 4 a and b as basic circuit diagrams.
  • the resistor R a 5 according to FIG. 2 has been replaced in FIG. 4 a by a switchable resistor 13 with two switch positions.
  • This switchable resistor 13 consists of two series-connected resistors 15 and 16 and a switch 17, which can be controlled by a signal HL 14, with two switch positions, one switch position bridging the resistor 16 (cf. FIG. 4b).
  • the switchable resistor 13 thus realizes two different series resistors depending on the switch position, namely either a resistor R a ⁇ corresponding to the resistor 15 or a resistor R a2 corresponding to the sum of the resistors 15 and 16.
  • Two load resistors can therefore be set.
  • the influences of R al and R a on the charging and discharging processes differ significantly from one another and, in the case of an unchanged sensor arrangement with an unchanged material, cause two different frequencies fi and
  • the alternative second embodiment is shown in Fig. 5 a and b. It differs from the first embodiment in that the modification to the circuit does not change the charge current, but rather the lower and upper voltage threshold values on the sensor.
  • the resistor 20 therefore corresponds to the resistor 10 from FIG. 2, while the resistor 11 in the resistor circuit is replaced by a series connection of the resistors 21 and 22, the resistor 22 being designed to be bridged by a switch 23, controlled by a switching signal 19.
  • the curve family 24 indicates the function with a small load resistance R a ⁇ , the capacitance C s being varied according to the horizontal x-axis up to 800 pF and the conductance of R s between 0 and 470 ⁇ S.
  • the family of curves 24 is reduced to a curve in FIG. 6, which indicates that the conductance of R s has no major influence on the function.
  • the family of curves 25, shows a comparable measurement, but with a different capacitance and a resistance R a2 , which has about 6 times the value of R ai .
  • Fig. 8 shows several charging curves as a time course of the signal 7 in V (vertical y-axis) over time in ⁇ s (horizontal x-axis). Furthermore, a threshold voltage is indicated as a horizontal line with the voltage value T.
  • the frequency explained at the outset which is composed of periodically successive charging and discharging processes, is influenced by the resistance R s as the voltage T increases as the threshold voltage for an interruption of the charging process ,
  • the sensor circuit is calibrated by integrating calibration capacitances C s and Ci 0n and resistors R s , k into the circuit and determining the respective frequencies f 1, k and f 2 k .
  • the measured frequencies fi and f 2 can then be assigned on the basis of table values and, if appropriate, linear interpolation, optimized variables for C s and R s .
  • a sensor is immersed in deionized water with a conductivity of 1 ⁇ S / cm (case d) and in normal tap water with a conductivity of 540 ⁇ S / cm (case n), the conductivities being in a conventional device of the prior art at a measuring frequency of 400 Hz.
  • the charging curves according to FIG. 8 are verified for the determination of the water content and the conductivity by recording them with a transient recorder or another data storage unit for evaluation.
  • the dielectric constant ⁇ m of the material and the conductivity ⁇ result from two settings Ei and E 2 , ie by determining two frequencies fi and f 2, ie two charging times.
  • the charge curve is calculated using the differential equation system for both Ei and E 2 , from which the corresponding frequencies, ie voltage value T, are determined and compared with fi and f 2 .
  • the input values C ⁇ and R s are changed again and a new employed immediately. This fit procedure is repeated until there is a match between the calculated and measured frequencies within a specified tolerance.
  • the values ⁇ m and ⁇ are calculated according to equations (3) and (2).
  • each with an insulated wire as an electrode are particularly suitable for the depth-resolved measurement of soil water content.
  • each of the two wires consists of several sections which are parallel to one another and which are arranged in a plane such that each section is adjacent to one electrode with two sections of the other electrode.
  • the resulting flat surface and the sensitive thickness, which depends on the wire distance, determines the sensitive volume of the sensor.
  • Sensors consisting of two insulated plates, which are inserted into the ground as electrodes in an upright position and parallel to one another, are preferably used when the depth resolution is irrelevant.
  • the vertical installation of the plates minimizes the interference of the sensors with the water movement in the floor.
  • Sensors consisting of two or more rigid, insulated electrodes which are pierced into the material are particularly suitable for use in bulk goods. This arrangement of the electrodes in the bulk material essentially corresponds to that of a TDR probe according to the prior art.
  • Time domain reflectometry simultaneous measurement of soil water content and electrical conductivity with single probe. Science 224: 989-990.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • General Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Medicinal Chemistry (AREA)
  • Food Science & Technology (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Remote Sensing (AREA)
  • Geology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

L'invention concerne un procédé permettant de déterminer la teneur en eau et la conductivité dans des sols et dans des produits en vrac. L'invention vise à proposer un procédé de ce type, se caractérisant par une complexité technique réduite. A cet effet, il est prévu un procédé comprenant les étapes suivantes : introduire un capteur capacitif (4) dans le sol ou dans le produit en vrac concerné ; charger ledit capteur avec une alimentation en tension extérieure constante par l'intermédiaire d'un courant initial pouvant être prédéfini, entre une première valeur-seuil de tension pouvant être prédéterminée et une seconde valeur-seuil de tension pouvant être prédéterminée, puis déterminer un diagramme en fonction de la tension et du temps, ou mesurer le premier temps de charge nécessaire à cet effet, entre les deux valeurs-seuils de tension et charger le capteur avec l'alimentation en tension extérieure constante, pour déterminer un second temps de charge, le courant initial et/ou au moins une des deux valeurs-seuils de tension étant modifiés ; déterminer la teneur en eau et la conductivité par vérification des deux temps de charge ou du diagramme en fonction de la tension et du temps.
EP03772275A 2002-11-30 2003-10-30 Procede et dispositif pour determiner la teneur en eau et la conductivite dans des sols et dans des produits en vrac Withdrawn EP1565735A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10256064A DE10256064B4 (de) 2002-11-30 2002-11-30 Verfahren und Vorrichtung zur Bestimmung des Wassergehalts und der Leitfähigkeit in Böden und Schüttgütern
DE10256064 2002-11-30
PCT/EP2003/012040 WO2004051248A1 (fr) 2002-11-30 2003-10-30 Procede et dispositif pour determiner la teneur en eau et la conductivite dans des sols et dans des produits en vrac

Publications (1)

Publication Number Publication Date
EP1565735A1 true EP1565735A1 (fr) 2005-08-24

Family

ID=32318859

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03772275A Withdrawn EP1565735A1 (fr) 2002-11-30 2003-10-30 Procede et dispositif pour determiner la teneur en eau et la conductivite dans des sols et dans des produits en vrac

Country Status (5)

Country Link
US (1) US7126352B2 (fr)
EP (1) EP1565735A1 (fr)
AU (1) AU2003279330A1 (fr)
DE (1) DE10256064B4 (fr)
WO (1) WO2004051248A1 (fr)

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1411349B1 (fr) * 2002-10-18 2005-12-21 Siemens Schweiz AG Sonde d'humidité avec un capteur capacitif d'humidité et méthode de mesure de l'humidité atmosphérique
JP2004150960A (ja) * 2002-10-30 2004-05-27 Nichirei Corp 物性測定用プローブ
CA2486562A1 (fr) * 2004-11-26 2006-05-26 Moustafa Mohamed Appareil pour determiner les proprietes electriques d'un echantillon
US7836910B2 (en) 2004-12-29 2010-11-23 Rain Bird Corporation Soil moisture sensor and controller
US7863562B2 (en) * 2007-06-22 2011-01-04 Shimadzu Corporation Method and apparatus for digital differential ion mobility separation
US7562832B1 (en) * 2008-01-17 2009-07-21 Technical Development Consultants, Inc. Two-conductor moisture activated switch
US8756828B2 (en) * 2008-05-01 2014-06-24 Whirlpool Corporation Failure mode detection in an appliance dispensing system
DE102009011278B4 (de) * 2009-03-05 2017-04-20 Imko Micromodultechnik Gmbh Sonde sowie Vorrichtung zur Ermittlung der Materialfeuchte oder Leitfähigkeit eines Mediums
JP2012058014A (ja) * 2010-09-07 2012-03-22 Ngk Insulators Ltd 粒子状物質検出装置
US20120139565A1 (en) * 2010-12-03 2012-06-07 Polygon Us Corporation Moisture sensing
GB201021033D0 (en) * 2010-12-13 2011-01-26 Verdirrigation Ltd An irrigation apparatus and a sensor therefor
JP5447496B2 (ja) * 2011-12-19 2014-03-19 株式会社デンソー 静電容量式タッチセンサ制御装置
JP6150437B2 (ja) * 2014-05-14 2017-06-21 公益財団法人鉄道総合技術研究所 土壌中の含水比の測定方法
US9909987B1 (en) 2014-07-30 2018-03-06 Transcend Engineering and Technology, LLC Systems, methods, and software for determining spatially variable distributions of the dielectric properties of a material
US9970969B1 (en) 2014-08-26 2018-05-15 Transcend Engineering and Technology, LLC Systems, methods, and software for determining spatially variable distributions of the dielectric properties of a heterogeneous material
JP6175040B2 (ja) * 2014-10-21 2017-08-02 公益財団法人鉄道総合技術研究所 土壌中の含水比の測定方法
CH712638B1 (de) 2016-06-30 2020-07-15 Wunderli Electronics Ag Messverfahren und Messvorrichtung für eine Flüssigkeitsmeldeanlage.
WO2019082763A1 (fr) * 2017-10-23 2019-05-02 国立大学法人静岡大学 Capteur de sol et procédé de mesure du sol
NL2021169B1 (en) * 2018-06-22 2020-01-06 Sensoterra B V Sensing probe for sensing a parameter of the ground at a certain depth, methods for placing and using such probes

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3155899A (en) * 1957-02-26 1964-11-03 Industrial Nucleonics Corp Method and apparatus for determining moisture content and other variables utilizing a capacitor test cell at two different frequencies
US3715656A (en) * 1971-05-27 1973-02-06 Ici Ltd Method and apparatus for measuring the charge-time response of materials by applying a voltage step across the same
US4426616A (en) * 1981-10-06 1984-01-17 Simmonds Precision Products, Inc. Capacitive measurement system
US4616425A (en) * 1983-01-27 1986-10-14 Iowa State University Research Foundation Moisture measurement apparatus and method
US4683904A (en) * 1984-08-30 1987-08-04 Ranya L. Alexander Moisture sensor
DE3817504A1 (de) * 1987-05-29 1989-02-23 Oswald Kopp Rechteck-generator
US5218309A (en) * 1990-06-25 1993-06-08 The United States Of America As Represented By The Secretary Of Agriculture Single kernel, seed, nut, or fruit dielectric moisture content measurement
EP0552275B1 (fr) 1990-10-12 1998-07-22 WATSON, Keith Detecteur d'humidite et de salinite et procede d'utilisation
US5224769A (en) * 1992-01-03 1993-07-06 University Of Florida Method and device for non-invasive monitoring of hydration state of plants
US6904789B2 (en) * 2001-07-13 2005-06-14 Decagon Devices, Inc. Moisture detection apparatus and method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2004051248A1 *

Also Published As

Publication number Publication date
WO2004051248A1 (fr) 2004-06-17
DE10256064B4 (de) 2004-10-28
DE10256064A1 (de) 2004-06-17
AU2003279330A1 (en) 2004-06-23
US7126352B2 (en) 2006-10-24
US20050212532A1 (en) 2005-09-29

Similar Documents

Publication Publication Date Title
DE10256064B4 (de) Verfahren und Vorrichtung zur Bestimmung des Wassergehalts und der Leitfähigkeit in Böden und Schüttgütern
EP2100101B1 (fr) Système pour mesurer une grandeur physique
EP2962074B1 (fr) Procédé et dispositif de surveillance d'un niveau prédéterminé d'un milieu dans un récipient
EP3152530A1 (fr) Procédé de surveillance du niveau de remplissage d'un milieu dans un récipient
DE102010049488B4 (de) Verfahren zum Testen eines Laborgeräts und entsprechend ausgestattetes Laborgerät
EP0753755A2 (fr) Dispositif de mesure de la constante diélectrique complexe du tabac
DE69018193T2 (de) Verfahren und Apparatur zur Untersuchung des Zustandes eines Isolationssystems.
EP3652508A1 (fr) Procédé de mesure capacitive et dispositif de mesure de niveau
DE10063557B4 (de) Verfahren und Vorrichtung zum Messen von Pegelständen
EP4134637B1 (fr) Sonde capacitive de niveau de remplissage sans zone morte
EP1255969B1 (fr) Dispositif permettant de determiner le niveau de remplissage d'un agent dans un contenant
EP0911628B1 (fr) Capteur pour la détermination de la teneur en eau
DE2021811C3 (de) Einrichtung zur Messung der Dielektrizitätskonstanten von Stoffen
DE3329025A1 (de) Verfahren und einrichtung zum bestimmen des feuchtegehalts von getreide und anderen koernigen stoffen
WO2019105657A1 (fr) Procédé de surveillance de processus
EP0724140B2 (fr) Procédé et dispositif pour l'évaluation des signaux d'un capteur de niveau capacitif
DE2924556A1 (de) Fuellstandsanzeigeeinrichtung
WO2023160958A1 (fr) Procédé et dispositif de surveillance du niveau de remplissage d'un milieu dans un récipient
WO2023161064A1 (fr) Détermination de conductivité compensée
EP3521778A1 (fr) Capteur d'impédance et son procédé de fonctionnement
EP3556600A1 (fr) Dispositif et procédé d'étalonnage de dispositifs de détection d'objets
DE1801033C (de) Vorrichtung zur Eichung mindestens einer Strahlungsintensitätsmeßvorrichtung
DE102009001695A1 (de) Verfahren zur Impedanzmessung
DE2030377A1 (de) Verfahren und Einrichtung zur Messung der Feuchtigkeit von sich be wegenden dielektrischen Stoffen

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20050331

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK

DAX Request for extension of the european patent (deleted)
RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: HELMHOLTZ ZENTRUM MUENCHEN DEUTSCHES F

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: HELMHOLTZ ZENTRUM MUENCHEN DEUTSCHES F

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20090918