Design and development of improved linearized network based liquid level transmitter
01 Nov 2013-pp 1-6
TL;DR: In this paper, a liquid level transmitter using cylindrical capacitive sensor and an improved linearized network for capacitance measurement has been proposed to measure the liquid level and to convert level changes into an electrical current which can be transmitted to a remote indicator.
Abstract: In this paper, a liquid level transmitter using cylindrical capacitive sensor and an improved linearized network for capacitance measurement has been proposed to measure the liquid level and to convert level changes into an electrical current which can be transmitted to a remote indicator. The change in capacitance of cylindrical capacitive sensor due to change in liquid level is measured by an improved linearized capacitance measuring network. The offset capacitance of the cylindrical capacitive sensor and the stray capacitances that exist between sensor electrodes & metallic tank are measured before the liquid level measurement. The measured capacitances are used in the proposed capacitance measuring network to minimize the effects of offset capacitance and stray capacitances on liquid level measurement using dc control voltage and operational amplifiers with high input impedance. The experimental investigations have been performed to sense water level of metallic tank in both increased and decreased level conditions. In the first phase of experiment, a linearized network has been simulated using LabVIEW (Laboratory Virtual Instrument Engineering Workbench) and studied with the test capacitance, and in the second phase, the experimentation was done by replacing the test capacitance with a cylindrical capacitive sensor for the measurement of liquid level. As a result of investigations conducted, it has been observed that the variation in liquid level from 0 to 25cm having linear relationship with output dc voltage in the range of 0 to 5.5V. Corresponding to liquid level variations, the dc output voltage further converted into an electric current of 4 to 20mA for remote indication and control purpose. The experimental results of liquid level transmitter are found to have good linearity of about ± 0.2% and a resolution of about 1 cm. The sensitivities of the capacitance measuring circuit and level transmitter have been found about 6.5 mV/pF and 250mV/cm respectively.
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17 Mar 2015
TL;DR: The experimental results indicate that the accuracy of the proposed experimental prototype sensor is equivalent to that of a commercially available ultrasound water level sensor, while, additionally, its manufacturing cost is significantly lower.
Abstract: Water-level sensors are indispensable for monitoring the level of water in storage tanks, which are used in drinking water distribution networks. In this paper, a long-range capacitive-type water-level sensor is presented. The proposed sensor is constructed using widely-available multilayer tubes, which are used for building drinking water systems. Thus, both the manufacturing cost of the sensor and the cost of the associated electronic circuits, which are used for interfacing the sensor to a digital data-acquisition unit, are low. The performance of the proposed sensor has been evaluated in a water storage tank of a city-scale water distribution network. The experimental results indicate that the accuracy of the proposed experimental prototype sensor is equivalent to that of a commercially available ultrasound water level sensor, while, additionally, its manufacturing cost is significantly lower.
38 citations
Cites methods from "Design and development of improved ..."
...Cylindrical capacitive electrodes were developed in [6] for a liquid-level sensor....
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TL;DR: This paper has thoroughly reviewed the conventional as well as optical techniques of the liquid-level measurement and transmitting technologies of the measured quantity and concludes with a conclusion about transmitting technologies.
Abstract: Liquid-level measurement in storage tank system play an important role in industrial application such as in food processing, pharmaceutical industry, chemical industry, water purification system, p...
14 citations
Cites methods from "Design and development of improved ..."
...Other transmitting technologies include converting DC voltage value into varying electric current form of 4–20mA [77]....
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01 Jan 2016
TL;DR: This paper presents a technique for analyzing the amount of additives added to the liquid, whose level is to be controlled, and design a multi sensor framework to achieve objectives.
Abstract: This paper presents a technique for analyzing the amount of additives added to the liquid, whose level is to be controlled. The objective of the proposed work is to design a technique which will (i) measure level of liquid independent of solution, (ii) analyze the quantity of additives present in the solution and (iii) design a multi sensor framework to achieve objectives (i) and (ii). Capacitive Level Sensor (CLS) and Ultrasonic Level Sensor (ULS) are used for measurement of liquid level. Respective data conversion circuits are designed to convert output of both the sensor to a standard signal (voltage). For incorporation of Multi Sensor Data Fusion (MSDF) Joint Defense Labortory (JDL) framework is considered. Once the system is designed it is tested with data. Results obtained shows successful implementation of proposed work.
7 citations
Cites methods from "Design and development of improved ..."
...Development of calibration technique for linearizing the output of liquid level transmitter using neural network algorithm is discussed in [6]....
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01 Jan 2017
TL;DR: The design proposed here uses three capacitive sensors and a capacitance to digital converter IC integrated onto a sensor Printed Circuit Board to solve the problem of liquid level sensing and monitoring using capacitive sensing techniques.
Abstract: This paper presents the design of a level sensor for the purpose of liquid level sensing and monitoring using capacitive sensing techniques. Conventional techniques have many drawbacks with respect to accuracy and they cannot be used reliably for remote sensing. The design proposed here uses three capacitive sensors and a capacitance to digital converter IC integrated onto a sensor Printed Circuit Board. The sensor PCB is attached to the walls of the container and this allows the measurements to be made without any contact with the liquid. The sensing mechanism is independent of the liquid or the environment in which it is placed. The levels are uploaded onto a database located at a local server, and this data can be easily accessed by the user as per his requirement. Further, an android application has been developed for monitoring the liquid levels conveniently.
References
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Book•
01 Aug 1996
TL;DR: Capacitive sensors in Silicon Technology as discussed by the authors have been shown to have high dielectric properties of various materials, including electret microphones, acceleration sensors, and sensors with different types of connectors.
Abstract: Preface Introduction Electrostatics Capacitive Sensor Basics Circuit Basics APPLICATIONS Capacitive Micrometers Proximity Detectors Motion Encoders Multiple Plate Systems Miscellaneous Sensors DESIGN Circuits and Components Switched Capacitor Techniques Noise and Stability Hazards PRODUCTS Electret Microphone Accelerometer StudSensor Proximity Detector Vernier Caliper Graphic Input Tablet Camera Positioner Digital Level References Appendix 1--Capacitive Sensors in Silicon Technology Appendix 2--Dielectric Properties of Various Materials Index
695 citations
Book•
01 Jan 2003
TL;DR: In this article, the authors present a detailed description of the characteristics of a flowmetering system and its application in a variety of applications, including the following: anemometers BTU Flowmeters for Heat Exchangers BTUs for Gaseous Fuels Cross-Correlation Flow Metering Elbow Taps Flow Switches Jet Deflection Flow Detectors Laminar Flow Meters, Magnetic FlowMeters, Coriolis Mass Flow-meters-Miscellaneous Mass Flowmetmers-Thermal Metering Pumps Orifices Pitot Tubes and
Abstract: GENERAL CONSIDERATIONS Flowsheet Symbols and P&I Diagrams Functional Diagrams and Function Symbols Instrument Terminology and Performance System Accuracy Uncertainty Calculations Configuring Intelligent Devices Instrument Installation Instrument Calibration Response Time and Drift Testing Redundant and Voting Systems Instrument Evaluation Binary Logic Diagrams FLOW MEASUREMENT Application and Selection Anemometers BTU Flowmeters for Heat Exchangers BTU Flowmeters for Gaseous Fuels Cross-Correlation Flow Metering Elbow Taps Flow Switches Jet Deflection Flow Detectors Laminar Flowmeters Magnetic Flowmeters Mass Flowmeters, Coriolis Mass Flowmeters-Miscellaneous Mass Flowmeters-Thermal Metering Pumps Orifices Pitot Tubes and Area Averaging Units Polyphase (Oil/Water/Gas) Flowmeters Positive-Displacement Gas Flowmeters Positive-Displacement Liquid Meters and Provers Purge Flow Regulators Segmental Wedge Flowmeter Sight Flow Indicators Solids Flowmeters and Feeders Target Meters Turbine and Other Rotary Element Flowmeters Ultrasonic Flowmeters Variable-Area, Gap, and Vane Flowmeters V-Cone Flowmeter Venturi Tubes, Flow Tubes, and Flow Nozzles Vortex and Fluidic Flowmeters Weirs and Flumes LEVEL MEASUREMENT Application and Selection Bubblers Capacitance and Radio Frequency (RF) Admittance Probes Conductivity and Field Effect Level Switches Diaphragm Level Detectors Differential Pressure Level Detectors Displacer Level Detectors Float Level Devices Laser Level Sensors Level Gauges, Including Magnetic Microwave Level Switches Optical Level Devices Radar, Noncontacting Level Sensors Radar, Contact Level Sensors (TDR, GWR, PDS) Radiation Level Sensors Resistance Tapes Rotating Paddle Switches Tank Gauges Including Float-Type Tape Gauges Thermal Level Sensors Time Domain Reflectometry and Phase Difference Sensors Ultrasonic Level Detectors Vibrating Level Switches TEMPERATURE MEASUREMENT Application and Selection Bimetallic Thermometers Calibrators and Simulators Color Indicators, Crayons, Pellets Fiber-Optic Thermometers Filled-Bulb and Glass-Stem Thermometers Integrated Circuitry (IC) Transistors and Diodes Miscellaneous Temperature Sensors Pneumatic and Suction Pyrometers Pyrometric Cones Radiation and Infrared Pyrometers Quartz Crystal Thermometry Resistance Temperature Detectors (RTDs) Temperature Switches and Thermostats Thermistors Thermocouples Thermowells Ultrasonic Thermometers PRESSURE MEASUREMENT Selection and Application Accessories: Seals, Snubbers, Calibrators, and Manifolds Bellows-Type Pressure Sensors Bourdon and Helical Pressure Sensors Diaphragm or Capsule-Type Sensors Differential Pressure Instruments Electronic Pressure Sensors High-Pressure Sensors Manometers Multiple Pressure Scanners Multiple Pressure Scanners Pressure Gauges Pressure Repeaters Pressure and Differential Pressure Switches Vacuum Sensors DENSITY MEASUREMENT Density: Applications and Selection Displacement- and Float-Type Densitometers Hydrometers Hydrostatic Densitometers Oscillating Coriolis Densitometer (Gas, Liquid, and Slurry Services) Radiation Densitometers Ultrasonic Sludge and Slurry Densitometers Liquid/Slurry/Gas Density-Vibrating Densitometers Weight-Based and Miscellaneous Densitometers Gas Densitometers SAFETY AND MISCELLANEOUS SENSORS Boroscopes Electrical and Intrinsic Safety Electrical Meters and Sensors Energy Management Devices (Peak Load Shedding) Excess Flow and Regular Check Valves Explosion Suppression and Deluge Systems Flame Arresters, Conservation Vents, and Emergency Vents Flame, Fire, and Smoke Detectors Leak Detectors Linear and Angular Position Detection Machine Vision Technology Metal Detectors Noise Sensors Proximity Sensors and Limit Switches Relief Valves-Determination of Required Capacity Relief Valves-Sizing, Specification, and Installation Rupture Discs Soft Sensors Tachometers and Angular Speed Detectors Thickness and Dimension Measurement Torque and Force Transducers Vibration, Shock, and Acceleration Weather Stations Weighing Systems: General Considerations Weight Sensors ANALYTICAL INSTRUMENTATION Analyzer Application and Selection Analyzer Sampling: Process Samples Analyzer Sampling: Stack Particulates Analyzers Operating on Electrochemical Principles Air Quality Monitoring Biometers Biochemical Oxygen Demand, Chemical Oxygen Demand, and Total Oxygen Demand Calorimeters Carbon Dioxide Carbon Monoxide Chlorine Chromatographs: Gas Chromatographs: Liquid Coal Analyzers Colorimeters Combustibles Conductivity Analyzers Consistency Analyzers Corrosion Monitoring Differential Vapor Pressure Sensor Dioxin Analysis Elemental Monitors Fiber-Optic Probes Fluoride Analyzers Hydrocarbon Analyzers Hydrogen Sulfide Infrared Analyzers Ion-Selective Electrodes Mass Spectrometers Mercury in Air Mercury in Water Moisture in Air: Humidity and Dew Point Moisture in Gases and Liquids Moisture in Solids Molecular Weight Nitrate, Ammonia, and Total Nitrogen Nitrogen Oxide Analyzers Odor Detection Oil in or on Water Open Path Spectrometry Oxidation-Reduction Potential (ORP) Oxygen in Gases Oxygen in Liquids (Dissolved Oxygen) Ozone in Gas Ozone in Water Particulates, Opacity, Dust, and Smoke Particle Size and Distribution Monitors pH Measurement Phosphorus Analyzer Physical Properties Analyzers - ASTM Methods Raman Analyzers Refractometers Rheometers Streaming Current or Particle Charge Analyzer Sulfur-in-Oil Analyzers Sulfur Oxide Analyzers Thermal Conductivity Detectors Total Carbon Analyzers Toxic Gas Monitoring Turbidity, Sludge, and Suspended Solids Ultraviolet and Visible Analyzers Viscometers-Application and Selection Viscometers-Laboratory Viscometers-Industrial Water Quality Monitoring Wet Chemistry and Autotitrator Analyzers APPENDIX International System of Units Engineering Conversion Factors Chemical Resistance of Materials Composition of Metallic and Other Materials Steam and Water Tables Friction Loss in Pipes Tank Volumes Directory of "Lost" Companies INDEX
93 citations
"Design and development of improved ..." refers background in this paper
...Hence, various attempts have been made by different investigators [3]–[17] to accurately measure this change in capacitance....
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TL;DR: In this article, a stray-immune capacitance measuring instrument based on the charge transfer principle is described, which has a programmable measurement frequency up to several megahertz and is inexpensive and suitable for integration onto a single chip.
Abstract: A stray-immune capacitance measuring instrument based on the charge transfer principle is described. It has a programmable measurement frequency up to several megahertz and is inexpensive and suitable for integration onto a single chip. The effects of stray capacitances, including those of the switching components, have been eliminated by using a special switching arrangement, resulting in a baseline drift of 0.02 pF (at 1-MHz measurement frequency) over a 12-h period. >
91 citations
01 Jan 2011
TL;DR: The optimization needed to improve the overall performance of the alignment system, making it suitable for use in commercial applications is presented.
Abstract: Capacitive sensors are a good choice for sub nanometer-resolu tion position measurements, but their performance is dependent on the correct alignment. Therefore, a capacitive sensor with an integrated self-alignment system has been developed which enables the use of capacitive sensors without alignment problems due to mounting and fabrication tolerance. The thermally actuated self-alignment system used has been proven to be functional. This paper presents the optimization needed to improve the overall performance of the alignment system, making it suitable for use in commercial applications. Parameters such as design geometry, input power and material have been used to optimize the system to meet specifications like speed, stability and resolution. Basic design rules for the system have been modelled in Matlab. The validity of this model has been verified by experimental results.
81 citations
"Design and development of improved ..." refers background in this paper
...Capacitive sensors [1] electronically measure the capacitance between two or more conductors in a dielectric environment, usually air or a liquid....
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