AU2002219098A1 - Method and device for determining and/or monitoring the level of a medium in a container, or for determining the density of a medium in a container - Google Patents

Method and device for determining and/or monitoring the level of a medium in a container, or for determining the density of a medium in a container

Info

Publication number
AU2002219098A1
AU2002219098A1 AU2002219098A AU1909802A AU2002219098A1 AU 2002219098 A1 AU2002219098 A1 AU 2002219098A1 AU 2002219098 A AU2002219098 A AU 2002219098A AU 1909802 A AU1909802 A AU 1909802A AU 2002219098 A1 AU2002219098 A1 AU 2002219098A1
Authority
AU
Australia
Prior art keywords
determining
container
density
medium
vibrating
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.)
Abandoned
Application number
AU2002219098A
Inventor
Sergej Lopatin
Alexander Muller
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.)
Endress and Hauser SE and Co KG
Original Assignee
Endress and Hauser SE and Co KG
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 Endress and Hauser SE and Co KG filed Critical Endress and Hauser SE and Co KG
Publication of AU2002219098A1 publication Critical patent/AU2002219098A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
    • G01F23/28—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring the variations of parameters of electromagnetic or acoustic waves applied directly to the liquid or fluent solid material
    • G01F23/296—Acoustic waves
    • G01F23/2966—Acoustic waves making use of acoustical resonance or standing waves
    • G01F23/2967—Acoustic waves making use of acoustical resonance or standing waves for discrete levels

Landscapes

  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Electromagnetism (AREA)
  • Thermal Sciences (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)
  • Automatic Analysis And Handling Materials Therefor (AREA)

Abstract

Method for determining or monitoring the height of a liquid in a container or for determining the liquid density. Method is based on setting a measurement body (4) vibrating and from the vibration response, determination of fluid height or density. The method compensates for the influence of external values, such as pressure or temperature on the vibration frequency of the vibrating body. Compensation method is based on determination of characteristic curves for the frequency change in the vibrating body caused by a change in pressure and temperature or in the viscosity. These are then used to adjust the measured frequencies of the vibrating body. An independent claim is made for a device for compensating for pressure, temperature or viscosity changes on a vibrating sensor level or density gauge.
AU2002219098A 2000-11-22 2001-11-13 Method and device for determining and/or monitoring the level of a medium in a container, or for determining the density of a medium in a container Abandoned AU2002219098A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10057974 2000-11-22
DE10057974A DE10057974A1 (en) 2000-11-22 2000-11-22 Determination of liquid level in a container or density of liquid in a container using a vibrating gimbal type body with compensation for temperature, pressure or viscosity variations to improve measurement accuracy
PCT/EP2001/013114 WO2002042724A1 (en) 2000-11-22 2001-11-13 Method and device for determining and/or monitoring the level of a medium in a container, or for determining the density of a medium in a container

Publications (1)

Publication Number Publication Date
AU2002219098A1 true AU2002219098A1 (en) 2002-06-03

Family

ID=7664263

Family Applications (1)

Application Number Title Priority Date Filing Date
AU2002219098A Abandoned AU2002219098A1 (en) 2000-11-22 2001-11-13 Method and device for determining and/or monitoring the level of a medium in a container, or for determining the density of a medium in a container

Country Status (6)

Country Link
US (1) US6845663B2 (en)
EP (1) EP1336083B1 (en)
AT (1) ATE370392T1 (en)
AU (1) AU2002219098A1 (en)
DE (2) DE10057974A1 (en)
WO (1) WO2002042724A1 (en)

Families Citing this family (98)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10237931A1 (en) * 2002-08-14 2004-02-26 Endress + Hauser Gmbh + Co. Kg Fixed, filling level monitoring, density, and viscosity measurement device, comprises a vibrator fixed at a chosen level, with a microprocessor to control feedback electronics to provide a constant phase-frequency response
DE10302437B4 (en) * 2003-01-21 2006-10-05 Endress + Hauser Gmbh + Co. Kg Device for monitoring a predetermined level of a medium in a container
DE10308087A1 (en) * 2003-02-24 2004-09-09 Endress + Hauser Gmbh + Co. Kg Protection against the effects of condensate bridges
DE10328296A1 (en) 2003-06-23 2005-01-20 Endress + Hauser Gmbh + Co. Kg Approach alarm for field devices
DE10331428B4 (en) * 2003-07-10 2005-07-28 Endress + Hauser Gmbh + Co. Kg Field device for determining and / or monitoring a process variable
US7272525B2 (en) * 2004-04-21 2007-09-18 Visyx Technologies, Inc. Portable fluid sensing device and method
DE102004036018A1 (en) * 2004-07-23 2006-02-16 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring at least one process variable
GB0420181D0 (en) * 2004-09-10 2004-10-13 Dt Assembly & Test Europ Ltd Metering apparatus
DE102004055552B4 (en) * 2004-11-17 2014-02-13 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring a fill level
DE102005015546A1 (en) * 2005-04-04 2006-10-05 Endress + Hauser Gmbh + Co. Kg Liquid medium`s process variable e.g. level, measuring device for e.g. monitoring process variable, has detection unit provided to determine and/or control pressure in direction perpendicular to diaphragm by vibrating diaphragm
DE102005015547A1 (en) * 2005-04-04 2006-10-05 Endress + Hauser Gmbh + Co. Kg Medium e.g. liquid`s, process variable determining and monitoring device, has receiving unit converting oscillations to reception signals, and all-pass filter adjusting phase difference between excitation and reception signals
DE102005062001A1 (en) * 2005-12-22 2007-06-28 Endress + Hauser Gmbh + Co. Kg Gaseous medium`s measured value determination and/or monitoring method, involves determining characteristic of oscillations of mechanically oscillatable unit, and determining measured value based on comparison of characteristic with curve
EP1804048B1 (en) * 2005-12-30 2010-05-12 Services Pétroliers Schlumberger A density and viscosity sensor
DE102006007199A1 (en) * 2006-02-15 2007-08-16 Vega Grieshaber Kg Vibration limit switch arrangement or method for correcting a vibration limit switch switching point
US20070186646A1 (en) * 2006-02-15 2007-08-16 Vega Grieshaber Kg Vibratory limit switch configuration and a process for correcting the switching point of a vibratory limit switch
DE102006033819A1 (en) 2006-07-19 2008-01-24 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring a process variable of a medium
DE102006034105A1 (en) 2006-07-20 2008-01-24 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring a process variable of a medium
US8261615B2 (en) * 2007-01-16 2012-09-11 Endress + Hauser Gmbh + Co. Kg Apparatus for determining and/or monitoring a process variable of a medium
DE102007008669A1 (en) * 2007-02-20 2008-08-21 Endress + Hauser Gmbh + Co. Kg Method for determining and / or monitoring a process variable of a medium and corresponding device
DE102008043764A1 (en) * 2008-11-14 2010-05-20 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring a process variable
ES2367226T3 (en) 2009-04-29 2011-10-31 Nest International N.V. DEVICE FOR MEASURING THE DENSITY OF A FLUID.
DE102009029490B4 (en) * 2009-09-16 2023-09-28 Endress+Hauser SE+Co. KG Level measuring device
DE102010002608A1 (en) * 2009-12-29 2011-06-30 Endress + Hauser GmbH + Co. KG, 79689 Device for determining at least one process variable
DE102010030791A1 (en) 2010-07-01 2012-01-05 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring a process variable of a medium
CN103328974B (en) * 2010-07-16 2015-08-12 康奈尔大学 Based on the self calibration viscosity sensor of the microprobe that ultrasonic amplitude transformer activates
DE102010063146B4 (en) * 2010-12-15 2024-04-25 Endress+Hauser SE+Co. KG Device for determining at least one process variable
US8869612B2 (en) 2011-03-08 2014-10-28 Baxter International Inc. Non-invasive radio frequency liquid level and volume detection system using phase shift
SE536170C2 (en) * 2011-09-27 2013-06-11 Scania Cv Ab Measurement system for measuring the density and level of a liquid in a container
DE102011089808A1 (en) * 2011-12-23 2013-06-27 Endress + Hauser Flowtec Ag Method or measuring system for determining a density of a fluid
DE102012100728A1 (en) * 2012-01-30 2013-08-01 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring at least one process variable
WO2014056709A1 (en) 2012-10-11 2014-04-17 Endress+Hauser Flowtec Ag Measuring system for determining a volume flow and/or a volume flow rate of a medium flowing in a pipe line
DE102012109729A1 (en) 2012-10-12 2014-05-15 Endress + Hauser Flowtec Ag Measuring system for determining volumetric flow during measuring interval of total flowed volume of flowing medium, particularly liquid or gas, has vibration element for guiding flowing portion of medium, where vibration element has lumen
KR102135803B1 (en) * 2013-04-26 2020-07-20 마이크로 모우션, 인코포레이티드 Vibratory sensor and method of varying vibration in a vibratory sensor
EP2811269A1 (en) * 2013-06-06 2014-12-10 VEGA Grieshaber KG Multi-threshold measuring device
CN103323367A (en) * 2013-06-18 2013-09-25 广州天禾自动化实业有限公司 Sensor for detecting fluid characteristics
DE102013109277A1 (en) * 2013-08-27 2015-03-05 Endress + Hauser Gmbh + Co. Kg Device for determining or monitoring a process variable
DE102014111905B3 (en) * 2014-08-20 2016-01-21 Endress + Hauser Gmbh + Co. Kg Reconditioning of coated sensors
US10663386B2 (en) * 2014-12-19 2020-05-26 Micro Motion, Inc. Controlling a vibration of a vibratory sensor based on a phase error
WO2016109451A1 (en) 2014-12-29 2016-07-07 Concentric Meter Corporation Electromagnetic transducer
US10126266B2 (en) 2014-12-29 2018-11-13 Concentric Meter Corporation Fluid parameter sensor and meter
WO2016109447A1 (en) 2014-12-29 2016-07-07 Concentric Meter Corporation Fluid parameter sensor and meter
DE102015101891A1 (en) 2015-02-10 2016-08-11 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring at least one process variable of a medium
KR20160101419A (en) * 2015-02-17 2016-08-25 한국전자통신연구원 Device and method for liquid level measurement
DE102015102834A1 (en) 2015-02-27 2016-09-01 Endress + Hauser Gmbh + Co. Kg Vibronic sensor
DE102015103071B3 (en) * 2015-03-03 2015-11-12 Endress + Hauser Gmbh + Co. Kg Vibronic sensor with one actuator
DE102015104536A1 (en) 2015-03-25 2016-09-29 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring at least one process variable
DE102015104533A1 (en) 2015-03-25 2016-09-29 Endress + Hauser Gmbh + Co. Kg Electromagnetic drive / receiver unit for a field device of automation technology
GB2538233A (en) * 2015-05-08 2016-11-16 Rosemount Measurement Ltd Improvements in or relating to level switches
DE102015108845A1 (en) 2015-06-03 2016-12-08 Endress + Hauser Gmbh + Co. Kg Coating for a measuring device of process technology
DE102015112421A1 (en) * 2015-07-29 2017-02-02 Endress + Hauser Gmbh + Co. Kg Phase control unit for vibronic sensor
DE102015112543A1 (en) * 2015-07-30 2017-02-02 Endress+Hauser Gmbh+Co. Kg Device for determining and / or monitoring at least one process variable
DE102015112544A1 (en) * 2015-07-30 2017-02-02 Endress+Hauser Gmbh+Co. Kg Device for determining or monitoring a process variable
DE102015121621B4 (en) * 2015-12-11 2018-03-01 Endress+Hauser Gmbh+Co. Kg Device for the safe determination and / or monitoring of a process variable
DE102015122124A1 (en) 2015-12-17 2017-06-22 Endress+Hauser Gmbh+Co. Kg Vibronic sensor and measuring arrangement for monitoring a flowable medium
DE102016112309A1 (en) 2016-07-05 2018-01-11 Endress + Hauser Gmbh + Co. Kg Device for determining and / or monitoring at least one process variable
DE102016112308A1 (en) 2016-07-05 2018-01-11 Endress + Hauser Gmbh + Co. Kg Electromagnetic drive / receiver unit for a field device of automation technology
DE102016112743A1 (en) 2016-07-12 2018-01-18 Endress+Hauser Gmbh+Co. Kg Vibronic sensor
GB2552685A (en) 2016-08-03 2018-02-07 Rosemount Measurement Ltd Improvements in or relating to vibrating fork level switches
DE102016117194A1 (en) 2016-09-13 2018-03-15 Endress + Hauser Gmbh + Co. Kg Compensation of a phase shift of at least one component of an electronics of a vibronic sensor
DE102016120326A1 (en) 2016-10-25 2018-04-26 Endress+Hauser SE+Co. KG Method for condition monitoring of an electromechanical resonator
DE102016124365A1 (en) 2016-12-14 2018-06-14 Endress+Hauser SE+Co. KG Vibronic sensor with temperature compensation
DE102016124740A1 (en) 2016-12-19 2018-06-21 Endress+Hauser SE+Co. KG Vibronic sensor with noise compensation
DE102016125243A1 (en) 2016-12-21 2018-06-21 Endress+Hauser SE+Co. KG Vibronic sensor with temperature compensation
DE102017102550A1 (en) 2017-02-09 2018-08-09 Endress+Hauser SE+Co. KG Condition monitoring of a vibronic sensor
DE102017103001A1 (en) 2017-02-15 2018-08-16 Endress+Hauser SE+Co. KG Improved adhesive bond by microstructuring a surface
DE102017111392A1 (en) 2017-05-24 2018-11-29 Endress+Hauser SE+Co. KG Vibronic sensor with noise compensation
DE102017114315A1 (en) 2017-06-28 2019-01-03 Endress+Hauser SE+Co. KG Temperature determination with a vibronic sensor
DE102017115147A1 (en) 2017-07-06 2019-01-10 Endress+Hauser SE+Co. KG Condition monitoring of a coil in a sensor
DE102017130527A1 (en) 2017-12-19 2019-06-19 Endress+Hauser SE+Co. KG Vibronic sensor
DE102017130530A1 (en) 2017-12-19 2019-06-19 Endress+Hauser SE+Co. KG Method for condition monitoring of a vibronic sensor
DE102018115368A1 (en) * 2018-06-26 2020-01-02 Endress+Hauser SE+Co. KG Parameterization of a field device
DE102018127526A1 (en) 2018-11-05 2020-05-07 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102018128734A1 (en) 2018-11-15 2020-05-20 Endress+Hauser SE+Co. KG Vibronic sensor with temperature compensation
DE102019109487A1 (en) 2019-04-10 2020-10-15 Endress+Hauser SE+Co. KG Condition monitoring of a vibronic sensor
DE102019110821A1 (en) 2019-04-26 2020-10-29 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102019112866A1 (en) 2019-05-16 2020-11-19 Endress+Hauser SE+Co. KG Condition monitoring of a vibronic sensor
DE102019114174A1 (en) 2019-05-27 2020-12-03 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102019116150A1 (en) 2019-06-13 2020-12-17 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102019116152A1 (en) 2019-06-13 2020-12-17 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102019116151A1 (en) 2019-06-13 2020-12-17 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102019131485A1 (en) 2019-11-21 2021-05-27 Endress+Hauser SE+Co. KG Condition monitoring of a vibronic sensor
DE102019132021A1 (en) * 2019-11-26 2021-05-27 Vega Grieshaber Kg Vibration sensor with integrated temperature detection with a vibrating membrane
DE102020104065A1 (en) 2020-02-17 2021-08-19 Endress+Hauser SE+Co. KG Vibronic sensor with reduced susceptibility to gas bubble formation
DE102020104066A1 (en) 2020-02-17 2021-08-19 Endress+Hauser SE+Co. KG Vibronic sensor
DE102020105214A1 (en) 2020-02-27 2021-09-02 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102020116299A1 (en) 2020-06-19 2021-12-23 Endress+Hauser SE+Co. KG Balancing a vibronic sensor
DE102020116278A1 (en) 2020-06-19 2021-12-23 Endress+Hauser SE+Co. KG Vibronic multi-sensor
DE102020127077A1 (en) 2020-10-14 2022-04-14 Endress+Hauser SE+Co. KG Method of operating a vibronic sensor
DE202021103688U1 (en) 2021-07-08 2021-09-06 Endress+Hauser SE+Co. KG Condition monitoring of a vibronic sensor
DE102021122534A1 (en) 2021-08-31 2023-03-02 Endress+Hauser SE+Co. KG Vibronic multisensor
DE102021122533A1 (en) 2021-08-31 2023-03-02 Endress+Hauser SE+Co. KG Vibronic multisensor
DE102021126093A1 (en) 2021-10-07 2023-04-13 Endress+Hauser SE+Co. KG Decoupling unit for a vibronic sensor
DE102021126092A1 (en) 2021-10-07 2023-04-13 Endress+Hauser SE+Co. KG Vibronic multisensor
DE102021129416A1 (en) 2021-11-11 2023-05-11 Endress+Hauser SE+Co. KG Condition monitoring for a vibronic sensor
CN114199313B (en) * 2021-12-20 2023-06-02 上海铭控传感技术有限公司 Throw-in type liquid measurement system and measurement method
DE102022115592A1 (en) 2022-06-22 2023-12-28 Endress+Hauser SE+Co. KG Modular vibronic multisensor
DE102022115594A1 (en) 2022-06-22 2023-12-28 Endress+Hauser SE+Co. KG Modular vibronic multisensor
DE102022115591A1 (en) 2022-06-22 2023-12-28 Endress+Hauser SE+Co. KG Modular vibronic multisensor

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3170094A (en) 1961-05-29 1965-02-16 Roth Wilfred Liquid level indicator
GB2067756B (en) * 1980-01-15 1983-11-16 Marconi Co Ltd Liquid level measurement
LU84185A1 (en) * 1982-06-07 1983-09-02 Egemin Nv MEASURING DEVICE
DE3348119C2 (en) * 1983-10-11 1989-12-28 Endress U. Hauser Gmbh U. Co, 7864 Maulburg, De Device for ascertaining and/or monitoring a predetermined filling level in a container
DE3336991A1 (en) * 1983-10-11 1985-05-02 Endress U. Hauser Gmbh U. Co, 7867 Maulburg DEVICE FOR DETECTING AND / OR MONITORING A PREDICTED LEVEL IN A CONTAINER
NL8801836A (en) * 1988-07-20 1990-02-16 Enraf Nonius Delft DEVICE FOR DETERMINING THE LEVEL OF THE BOUNDARY AREA BETWEEN A FIRST AND A SECOND MEDIUM IN A RESERVOIR.
DE3833896A1 (en) * 1988-10-05 1990-04-12 Vega Grieshaber Gmbh & Co Frequency difference evaluation
DE4210705C2 (en) * 1992-04-01 1995-10-19 Grieshaber Vega Kg Frequency-voltage converter for vibration level detectors and method for converting an input signal into an output signal representing the input signal frequency
US6044694A (en) * 1996-08-28 2000-04-04 Videojet Systems International, Inc. Resonator sensors employing piezoelectric benders for fluid property sensing
EP0875741B1 (en) * 1997-04-30 2008-08-20 Endress + Hauser GmbH + Co. KG Device for determining/monitoring of a predefined liquid level in a container
US6236322B1 (en) * 1998-09-09 2001-05-22 Endress + Hauser Gmbh + Co. Apparatus for establishing and/or monitoring a predetermined filling level in a container
DE10014724A1 (en) * 2000-03-24 2001-09-27 Endress Hauser Gmbh Co Liquid level and density monitoring method employed in food, chemical industry, involves evaluating vibration of vibrating rods arranged immersed in liquid at two different modes and recognizing mass change in rods

Also Published As

Publication number Publication date
EP1336083A1 (en) 2003-08-20
ATE370392T1 (en) 2007-09-15
WO2002042724A1 (en) 2002-05-30
DE50112873D1 (en) 2007-09-27
US6845663B2 (en) 2005-01-25
DE10057974A1 (en) 2002-05-23
EP1336083B1 (en) 2007-08-15
US20040078164A1 (en) 2004-04-22

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