The document discusses different types of instruments used to measure acceleration, vibration, and density. It describes LVDT, piezoelectric, and strain gauge accelerometers. It also discusses vibration sensors, including accelerometers, strain gauges, velocity sensors, and gyroscopes. Finally, it covers various densitometers for measuring liquid and gas density, including displacement, float, and ultrasonic densitometers.
This document presents information on the characteristics of instruments. It discusses both static and dynamic characteristics. The main static characteristics described are accuracy, sensitivity, reproducibility, drift, static error, dead zone, precision, threshold, linearity, stability, range/span, bias, tolerance, and hysteresis. The dynamic characteristics covered are speed of response, fidelity, lag, and dynamic error. The document was created by five students and guided by a professor to provide an overview of important instrument characteristics.
esistance thermometers, also called resistance temperature detectors (RTDs), are sensors used to measure temperature. Many RTD elements consist of a length of fine wire wrapped around a ceramic or glass core but other constructions are also used. The RTD wire is a pure material, typically platinum, nickel, or copper. The material has an accurate resistance/temperature relationship which is used to provide an indication of temperature. As RTD elements are fragile, they are often housed in protective probes.
Resistance thermometers are constructed in a number of forms and offer greater stability, accuracy and repeatability in some cases than thermocouples. While thermocouples use the Seebeck effect to generate a voltage, resistance thermometers use electrical resistance and require a power source to operate. The resistance ideally varies nearly linearly with temperature per the Callendar–Van Dusen equation.
The platinum detecting wire needs to be kept free of contamination to remain stable. A platinum wire or film is supported on a former in such a way that it gets minimal differential expansion or other strains from its former, yet is reasonably resistant to vibration. RTD assemblies made from iron or copper are also used in some applications. Commercial platinum grades exhibit a temperature coefficient of resistance 0.00385/°C (0.385%/°C) (European Fundamental Interval).[7] The sensor is usually made to have a resistance of 100 Ω at 0 °C. This is defined in BS EN 60751:1996 (taken from IEC 60751:1995). The American Fundamental Interval is 0.00392/°C,[8] based on using a purer grade of platinum than the European standard. The American standard is from the Scientific Apparatus Manufacturers Association (SAMA), who are no longer in this standards field. As a result, the "American standard" is hardly the standard even in the US.
Lead-wire resistance can also be a factor; adopting three- and four-wire, instead of two-wire, connections can eliminate connection-lead resistance effects from measurements (see below); three-wire connection is sufficient for most purposes and is an almost universal industrial practice. Four-wire connections are used for the most precise applications.
The document discusses various pressure measurement instruments such as pressure gauges, pressure switches, differential pressure gauges, and pressure transmitters. It describes the measuring principles, components, installation guidelines, and factors to consider when selecting pressure instruments for applications involving gases, liquids, and other process media. Proper instrument selection and installation is important to ensure accurate pressure measurement over the operating temperature and pressure ranges.
RTDs measure temperature by detecting changes in electrical resistance of a wire as temperature varies. There are two types based on whether resistance increases or decreases with temperature. RTDs are used in bridge circuits where changes in resistance produce voltage changes proportional to temperature. Thermocouples use the Seebeck effect where different metals produce voltage when joined and subjected to a temperature gradient. Common types include J, K, B, S, T, and R which vary in sensitivity and measurable temperature range. Both RTDs and thermocouples require signal conditioning due to their small voltage outputs and are calibrated using a temperature indicator, controller, and oven.
The document discusses various methods for measuring liquid level, including direct and indirect methods. Direct methods involve devices that come into direct contact with the liquid, such as sight glasses, dipsticks, floats, and displacers. Indirect methods measure liquid level without contact, including hydrostatic pressure devices, electrical methods like capacitance probes, and technologies using lasers, microwaves, or ultrasound. Each method has advantages and limitations depending on the application and type of liquid.
We provide you Project Temperature Sensors – Types.You can choose the best of your choice and interest from the list of topics we suggested. All new project ideas that are appearing focuses to improve the knowledge of Engineering students.
https://www.elprocus.com
Visit our page to get more ideas on Project Report Format for Final Year Engineering Students these ideas developed by professionals.
Elprocus provides free verified electronic projects kits around the world with abstracts, circuit diagrams, and free electronic software. We provide guidance manual for Do It Yourself Kits (DIY) with the modules at best price along with free shipping.
This document discusses resistance temperature detectors (RTDs). It explains that RTDs detect changes in temperature by measuring changes in the electrical resistance of a wire as temperature varies. Common wire materials used in RTDs include platinum, nickel, copper, and others. RTDs offer advantages like a wide temperature measurement range, good accuracy, and long-term stability. They are often used in temperature measurement and control applications like furnaces and laboratories.
This document presents information on the characteristics of instruments. It discusses both static and dynamic characteristics. The main static characteristics described are accuracy, sensitivity, reproducibility, drift, static error, dead zone, precision, threshold, linearity, stability, range/span, bias, tolerance, and hysteresis. The dynamic characteristics covered are speed of response, fidelity, lag, and dynamic error. The document was created by five students and guided by a professor to provide an overview of important instrument characteristics.
esistance thermometers, also called resistance temperature detectors (RTDs), are sensors used to measure temperature. Many RTD elements consist of a length of fine wire wrapped around a ceramic or glass core but other constructions are also used. The RTD wire is a pure material, typically platinum, nickel, or copper. The material has an accurate resistance/temperature relationship which is used to provide an indication of temperature. As RTD elements are fragile, they are often housed in protective probes.
Resistance thermometers are constructed in a number of forms and offer greater stability, accuracy and repeatability in some cases than thermocouples. While thermocouples use the Seebeck effect to generate a voltage, resistance thermometers use electrical resistance and require a power source to operate. The resistance ideally varies nearly linearly with temperature per the Callendar–Van Dusen equation.
The platinum detecting wire needs to be kept free of contamination to remain stable. A platinum wire or film is supported on a former in such a way that it gets minimal differential expansion or other strains from its former, yet is reasonably resistant to vibration. RTD assemblies made from iron or copper are also used in some applications. Commercial platinum grades exhibit a temperature coefficient of resistance 0.00385/°C (0.385%/°C) (European Fundamental Interval).[7] The sensor is usually made to have a resistance of 100 Ω at 0 °C. This is defined in BS EN 60751:1996 (taken from IEC 60751:1995). The American Fundamental Interval is 0.00392/°C,[8] based on using a purer grade of platinum than the European standard. The American standard is from the Scientific Apparatus Manufacturers Association (SAMA), who are no longer in this standards field. As a result, the "American standard" is hardly the standard even in the US.
Lead-wire resistance can also be a factor; adopting three- and four-wire, instead of two-wire, connections can eliminate connection-lead resistance effects from measurements (see below); three-wire connection is sufficient for most purposes and is an almost universal industrial practice. Four-wire connections are used for the most precise applications.
The document discusses various pressure measurement instruments such as pressure gauges, pressure switches, differential pressure gauges, and pressure transmitters. It describes the measuring principles, components, installation guidelines, and factors to consider when selecting pressure instruments for applications involving gases, liquids, and other process media. Proper instrument selection and installation is important to ensure accurate pressure measurement over the operating temperature and pressure ranges.
RTDs measure temperature by detecting changes in electrical resistance of a wire as temperature varies. There are two types based on whether resistance increases or decreases with temperature. RTDs are used in bridge circuits where changes in resistance produce voltage changes proportional to temperature. Thermocouples use the Seebeck effect where different metals produce voltage when joined and subjected to a temperature gradient. Common types include J, K, B, S, T, and R which vary in sensitivity and measurable temperature range. Both RTDs and thermocouples require signal conditioning due to their small voltage outputs and are calibrated using a temperature indicator, controller, and oven.
The document discusses various methods for measuring liquid level, including direct and indirect methods. Direct methods involve devices that come into direct contact with the liquid, such as sight glasses, dipsticks, floats, and displacers. Indirect methods measure liquid level without contact, including hydrostatic pressure devices, electrical methods like capacitance probes, and technologies using lasers, microwaves, or ultrasound. Each method has advantages and limitations depending on the application and type of liquid.
We provide you Project Temperature Sensors – Types.You can choose the best of your choice and interest from the list of topics we suggested. All new project ideas that are appearing focuses to improve the knowledge of Engineering students.
https://www.elprocus.com
Visit our page to get more ideas on Project Report Format for Final Year Engineering Students these ideas developed by professionals.
Elprocus provides free verified electronic projects kits around the world with abstracts, circuit diagrams, and free electronic software. We provide guidance manual for Do It Yourself Kits (DIY) with the modules at best price along with free shipping.
This document discusses resistance temperature detectors (RTDs). It explains that RTDs detect changes in temperature by measuring changes in the electrical resistance of a wire as temperature varies. Common wire materials used in RTDs include platinum, nickel, copper, and others. RTDs offer advantages like a wide temperature measurement range, good accuracy, and long-term stability. They are often used in temperature measurement and control applications like furnaces and laboratories.
This document defines various types of pressure and units of pressure measurement. It describes how pressure is measured using mechanical devices like manometers, bourdon tubes, and diaphragms. Absolute, gauge, differential, and other pressures are defined. Common units include psi, kPa, inches of water and mercury. Pressure results from force over an area and is proportional to height and density of the fluid. Mechanical pressure sensors are converted to electrical signals using transducers like potentiometers and capacitors.
The definition of the capacitive transducer is to measure the displacement (how much distance it covers), pressure and other several physical quantities, these transducers are preferred. In these transducers, the capacitance between the plates is varied because of the distance between the plates, overlapping of plates, due to dielectric medium change, etc.
The document discusses various methods for measuring liquid levels in industrial processes and storage containers. It describes direct methods like sight glasses and float-operated gauges, as well as indirect methods such as hydrostatic pressure sensors and electrical techniques. RF capacitance level measurement is explained in detail, with descriptions of how capacitance changes based on the dielectric constant of the insulating material between conductive plates, allowing the measurement of liquid levels.
This document summarizes a differential pressure transmitter. It discusses that a differential pressure transmitter senses the difference in pressure between two ports and produces an output signal proportional to the calibrated pressure range. It then describes the construction of an industrial differential pressure transmitter, which has two housings, with the pressure sensing element in the bottom half and electronics in the top half. It also outlines the internal arrangement of the transmitter including the direct pressure sensing element, signal conditioning electronics, and 2-wire 4-20mA current output. Finally, some common uses and the advantages and disadvantages of differential pressure transmitters are listed.
1) The document discusses field transmitters, providing information on their introduction, classification, operation, installation guidelines, and specifications.
2) Transmitters are used to transmit sensor signals over long distances in a standardized format and include features like HART communication.
3) The document covers transmitter components, calibration procedures, and specifications for factors like range, output, power supply, and temperature limits.
Flow sensors measure the rate of fluid flow through pipes. The key properties affecting fluid flow are velocity, pipe size, friction, viscosity, specific gravity, and fluid condition. Measuring flow is important for process control and efficiency. Common types of flow meters include differential pressure meters (orifice, venturi, nozzle), Coriolis, vortex, ultrasonic, electromagnetic, and thermal meters. Each works on different principles and has advantages and limitations for different applications.
This document summarizes four common types of elastic pressure measurement instruments: bourdon tube pressure gauges, diaphragm pressure gauges, bellows pressure gauges, and capsules. It describes the construction, working principle, characteristics, advantages, and disadvantages of each type. Bourdon tube pressure gauges use an oval cross-section tube that contracts or expands to transmit pressure readings. Diaphragm pressure gauges use a thin circular plate that deflects upwards under pressure. Bellows pressure gauges use an expandable and collapsible bellows element attached to a linkage.
This document discusses various types of pressure transducers, including mechanical and electrical types. Mechanical transducers use an elastic element like a bourdon tube, bellows, or diaphragm to convert pressure to displacement. Electrical transducers add an electric element to convert the mechanical displacement to an electrical signal. Common electric elements are piezoelectric materials, strain gauges, capacitors, and inductive coils. Piezoelectric transducers actively generate a voltage in response to pressure, while other electrical transducers like strain gauges are passive and require an external power source to modulate their electrical properties.
This document discusses different methods of level measurement in industries. It describes direct methods like sight glass level indicators and float type level indicators. It also covers indirect, electrical methods like resistive and capacitive level indicators. Sight glasses use a graduated glass tube to directly measure liquid level in a tank. Float level indicators transmit float movement via a pulley system to indicate level on a scale. Resistive indicators use a float to change the resistance of a potentiometer proportional to level. Capacitive methods measure how liquid level affects capacitor properties in various configurations.
Liquid Level Measurement By Indirect MethodJaydeep Vakil
This ppt contains Differential Method for measuring of liquid level of storage tanks and vessels. Differential method is one of the indirect method for liquid level measurement..
Today's document discusses methods for measuring liquid and solid levels in containers. There are two main categories: continuous level monitoring and single point sensing. Continuous monitoring constantly measures levels while single point sensing detects levels only when they reach a predetermined point. Direct sensing devices like level gauges and transmitters measure actual levels while indirect devices like differential pressure transmitters sense a liquid property like pressure to determine level. Common direct sensing devices include tubular and reflex type level gauges as well as float switches.
Electronics measurement and instrumentation pptImranAhmad225
This document defines key concepts in measurement and instrumentation. It discusses the definition of metrology and engineering metrology. Measurement is defined as the process of numerical evaluation of a dimension or comparison to a standard. Some key methods of measurement discussed are direct, indirect, comparative, coincidence, contact, deflection, and complementary methods. The document also discusses units and standards, characteristics of measuring instruments like sensitivity, readability, range, accuracy, and precision. It defines uncertainty and errors in instruments.
introduction to flow,flow type,laminar,turbulent,one dimensional flow,two dimensional flow,type of flow measurement,flow measuring elements,orifices,nozzles,venturi,pitot tubes,limitations,advantages of the elements,application of elements
This document provides an overview of instrumentation and process control. It defines key terms like instrumentation, process, transducer, signal, loop, controller, and interlock. It describes common process parameters measured like pressure, level, temperature, and flow. It discusses primary measuring devices and principles for each process variable. It also covers control valves and automation systems like DCS, PLC, and SCADA.
In this u will study about
1.Working Principle
2.Parameter for CTT
3.Applications (in details)
4.Advantages
5.Disadvantages
of Capacitive Type Transducer
This document discusses various methods for measuring pressure, including absolute, gauge, differential, and static pressures. It focuses on static pressure measurement techniques, such as using manometers, pressure taps in walls, and static pressure probes. Pressure taps should be small and perpendicular to minimize errors from cavities and turbulence. Probe designs include cylinders, wedges, and disks, with accuracy depending on location of pressure ports, alignment with flow, and Mach number effects. Calibration curves are used to determine measurement errors at different flow conditions.
Basic Industrial Instruments Used for Flow measurnment.
Working , Construction and diagrams with detailed explanations.
Major type of Instruments are listed.
This document discusses thermistors, which are temperature sensing elements that measure temperature through changes in resistance. It describes how thermistors are constructed from sintered semiconductor materials and come in various shapes. The document outlines the working principle of thermistors, types including positive and negative temperature coefficient thermistors, advantages like low cost and high sensitivity, disadvantages such as non-linear output, and applications including current limiting devices, digital thermostats, and battery pack monitors.
This document discusses vibration sensors. It defines vibration sensors as sensors that measure linear velocity, displacement, proximity, or acceleration. Vibration sensors are used to detect problems in industrial machines early by measuring abnormal vibration. The document discusses different types of vibration sensors including velocity sensors, acceleration sensors, and proximity sensors. It provides examples of different technologies used in each type. The document also discusses characteristics to consider when selecting a vibration sensor like sensitivity range and frequency range. Finally, it provides a table matching industries to ideal sensor traits for different applications.
This document defines various types of pressure and units of pressure measurement. It describes how pressure is measured using mechanical devices like manometers, bourdon tubes, and diaphragms. Absolute, gauge, differential, and other pressures are defined. Common units include psi, kPa, inches of water and mercury. Pressure results from force over an area and is proportional to height and density of the fluid. Mechanical pressure sensors are converted to electrical signals using transducers like potentiometers and capacitors.
The definition of the capacitive transducer is to measure the displacement (how much distance it covers), pressure and other several physical quantities, these transducers are preferred. In these transducers, the capacitance between the plates is varied because of the distance between the plates, overlapping of plates, due to dielectric medium change, etc.
The document discusses various methods for measuring liquid levels in industrial processes and storage containers. It describes direct methods like sight glasses and float-operated gauges, as well as indirect methods such as hydrostatic pressure sensors and electrical techniques. RF capacitance level measurement is explained in detail, with descriptions of how capacitance changes based on the dielectric constant of the insulating material between conductive plates, allowing the measurement of liquid levels.
This document summarizes a differential pressure transmitter. It discusses that a differential pressure transmitter senses the difference in pressure between two ports and produces an output signal proportional to the calibrated pressure range. It then describes the construction of an industrial differential pressure transmitter, which has two housings, with the pressure sensing element in the bottom half and electronics in the top half. It also outlines the internal arrangement of the transmitter including the direct pressure sensing element, signal conditioning electronics, and 2-wire 4-20mA current output. Finally, some common uses and the advantages and disadvantages of differential pressure transmitters are listed.
1) The document discusses field transmitters, providing information on their introduction, classification, operation, installation guidelines, and specifications.
2) Transmitters are used to transmit sensor signals over long distances in a standardized format and include features like HART communication.
3) The document covers transmitter components, calibration procedures, and specifications for factors like range, output, power supply, and temperature limits.
Flow sensors measure the rate of fluid flow through pipes. The key properties affecting fluid flow are velocity, pipe size, friction, viscosity, specific gravity, and fluid condition. Measuring flow is important for process control and efficiency. Common types of flow meters include differential pressure meters (orifice, venturi, nozzle), Coriolis, vortex, ultrasonic, electromagnetic, and thermal meters. Each works on different principles and has advantages and limitations for different applications.
This document summarizes four common types of elastic pressure measurement instruments: bourdon tube pressure gauges, diaphragm pressure gauges, bellows pressure gauges, and capsules. It describes the construction, working principle, characteristics, advantages, and disadvantages of each type. Bourdon tube pressure gauges use an oval cross-section tube that contracts or expands to transmit pressure readings. Diaphragm pressure gauges use a thin circular plate that deflects upwards under pressure. Bellows pressure gauges use an expandable and collapsible bellows element attached to a linkage.
This document discusses various types of pressure transducers, including mechanical and electrical types. Mechanical transducers use an elastic element like a bourdon tube, bellows, or diaphragm to convert pressure to displacement. Electrical transducers add an electric element to convert the mechanical displacement to an electrical signal. Common electric elements are piezoelectric materials, strain gauges, capacitors, and inductive coils. Piezoelectric transducers actively generate a voltage in response to pressure, while other electrical transducers like strain gauges are passive and require an external power source to modulate their electrical properties.
This document discusses different methods of level measurement in industries. It describes direct methods like sight glass level indicators and float type level indicators. It also covers indirect, electrical methods like resistive and capacitive level indicators. Sight glasses use a graduated glass tube to directly measure liquid level in a tank. Float level indicators transmit float movement via a pulley system to indicate level on a scale. Resistive indicators use a float to change the resistance of a potentiometer proportional to level. Capacitive methods measure how liquid level affects capacitor properties in various configurations.
Liquid Level Measurement By Indirect MethodJaydeep Vakil
This ppt contains Differential Method for measuring of liquid level of storage tanks and vessels. Differential method is one of the indirect method for liquid level measurement..
Today's document discusses methods for measuring liquid and solid levels in containers. There are two main categories: continuous level monitoring and single point sensing. Continuous monitoring constantly measures levels while single point sensing detects levels only when they reach a predetermined point. Direct sensing devices like level gauges and transmitters measure actual levels while indirect devices like differential pressure transmitters sense a liquid property like pressure to determine level. Common direct sensing devices include tubular and reflex type level gauges as well as float switches.
Electronics measurement and instrumentation pptImranAhmad225
This document defines key concepts in measurement and instrumentation. It discusses the definition of metrology and engineering metrology. Measurement is defined as the process of numerical evaluation of a dimension or comparison to a standard. Some key methods of measurement discussed are direct, indirect, comparative, coincidence, contact, deflection, and complementary methods. The document also discusses units and standards, characteristics of measuring instruments like sensitivity, readability, range, accuracy, and precision. It defines uncertainty and errors in instruments.
introduction to flow,flow type,laminar,turbulent,one dimensional flow,two dimensional flow,type of flow measurement,flow measuring elements,orifices,nozzles,venturi,pitot tubes,limitations,advantages of the elements,application of elements
This document provides an overview of instrumentation and process control. It defines key terms like instrumentation, process, transducer, signal, loop, controller, and interlock. It describes common process parameters measured like pressure, level, temperature, and flow. It discusses primary measuring devices and principles for each process variable. It also covers control valves and automation systems like DCS, PLC, and SCADA.
In this u will study about
1.Working Principle
2.Parameter for CTT
3.Applications (in details)
4.Advantages
5.Disadvantages
of Capacitive Type Transducer
This document discusses various methods for measuring pressure, including absolute, gauge, differential, and static pressures. It focuses on static pressure measurement techniques, such as using manometers, pressure taps in walls, and static pressure probes. Pressure taps should be small and perpendicular to minimize errors from cavities and turbulence. Probe designs include cylinders, wedges, and disks, with accuracy depending on location of pressure ports, alignment with flow, and Mach number effects. Calibration curves are used to determine measurement errors at different flow conditions.
Basic Industrial Instruments Used for Flow measurnment.
Working , Construction and diagrams with detailed explanations.
Major type of Instruments are listed.
This document discusses thermistors, which are temperature sensing elements that measure temperature through changes in resistance. It describes how thermistors are constructed from sintered semiconductor materials and come in various shapes. The document outlines the working principle of thermistors, types including positive and negative temperature coefficient thermistors, advantages like low cost and high sensitivity, disadvantages such as non-linear output, and applications including current limiting devices, digital thermostats, and battery pack monitors.
This document discusses vibration sensors. It defines vibration sensors as sensors that measure linear velocity, displacement, proximity, or acceleration. Vibration sensors are used to detect problems in industrial machines early by measuring abnormal vibration. The document discusses different types of vibration sensors including velocity sensors, acceleration sensors, and proximity sensors. It provides examples of different technologies used in each type. The document also discusses characteristics to consider when selecting a vibration sensor like sensitivity range and frequency range. Finally, it provides a table matching industries to ideal sensor traits for different applications.
An accelerometer is a device that measures acceleration forces. It contains capacitive plates that move relative to each other in response to acceleration, changing capacitance. This capacitance change can be converted to a voltage proportional to acceleration. Accelerometers are used to measure vibration in many fields. They are specified by factors like range, sensitivity, bandwidth, and axes. Common types include capacitive, piezoelectric, and strain gauge accelerometers. Proper calibration ensures the electrical output accurately represents measured acceleration.
This document discusses various types of mechanical sensors and their applications. It describes sensors that measure mechanical phenomena like pressure, force, torque, inertia, and flow. Pressure sensors are used in applications like manometers, barometers, microphones, and automotive parts. Force and torque sensors can be used in control systems, testing equipment, and for measuring power transmission. Inertial sensors like accelerometers have applications in industry, military, vibration monitoring, and safety systems. Flow sensors measure flow rates using principles of heat transfer and are used in microsensors and velocimetry applications. The document provides details on common sensing techniques like piezoresistivity, piezoelectricity, capacitive, inductive and resonant techniques.
The document discusses various types of sensors and transducers used to measure physical properties such as position, temperature, force, and pressure. It describes common sensors like resistive position transducers, strain gauges, capacitive transducers, inductive transducers, and temperature sensors. It provides details on the basic principles and examples of linear variable differential transformers (LVDTs), resistance temperature detectors (RTDs), thermocouples, and thermistors.
Vibration sensors detect vibrations and convert them into electrical signals. There are two main types: contact sensors that must mount directly to the object, and non-contact sensors that measure vibrations without direct contact. Common contact sensors include piezoelectric accelerometers, piezoresistive accelerometers, and strain gauges. Common non-contact sensors include microphones, laser displacement sensors, and eddy current sensors. Vibration data can be analyzed in both the time and frequency domains to diagnose machine problems.
Sensors for Biomedical Devices and systemsGunjan Patel
This document provides an overview of sensors used in biomedical devices and systems. It begins by defining key terms like sensor, transducer, and actuator. It then discusses different types of sensors like active and passive sensors. Examples of commonly used biomedical sensors are presented. Sources of sensor error and important sensor terminology are explained. The document provides details on displacement transducers, piezoelectric transducers, and strain gauges. It also describes the Wheatstone bridge circuit configuration often used with biomedical sensors.
This document discusses energy sensors. It defines energy and different types of sensors. It then describes various energy sensors including mechanical energy sensors like accelerometers and force sensors, thermal energy sensors like thermocouples and thermistors, and heat flux sensors. The document highlights key characteristics and applications of different energy sensors.
Vibration measurement systems use vibrometers and other devices to measure properties of vibrating bodies like displacement, velocity, frequency, and acceleration. Vibrometers work by converting the measured quantity into an electrical signal displayed on screen. Common vibration measurement devices include vibrometers, accelerometers, and tachometers. Vibrometers measure displacement, accelerometers measure acceleration, and tachometers like the Fullarton and Fruhm determine frequency by detecting the natural frequency of vibrating reeds. Proper mounting of sensors is important to obtain accurate readings.
TRANSDUCERS CONVERTS ENERGY FROM ONE FORM TO ANOTHERSamueljidayi
The document discusses different types of transducers including passive transducers like strain gauges, LVDTs, and potentiometers. A strain gauge uses the variation in electrical resistance of its wires to sense strain produced by a force. An LVDT measures linear displacement using a transformer with three coils and a ferromagnetic core. A potentiometer acts as a voltage divider to provide an adjustable output voltage proportional to the position of a slider along a resistive track. Examples are provided to demonstrate calculations for determining displacement from LVDT output or resistance changes from strain gauges.
Here are the steps to solve this problem:
(i) A suitable biomedical application of a thermistor is to measure body temperature, such as in a medical thermometer. Thermistors are well-suited for this application because they can accurately and precisely detect small temperature changes in the body.
(ii) For the bridge circuit shown:
Let R = resistance of each leg
dR = small change in resistance of one thermistor
Rf = resistance of the feedback resistor
Vs = input voltage
Vo = output voltage
Using Kirchhoff's voltage law on the mesh containing Rf, we get:
Vs = (R+dR)I1 + (R-
This document provides an introduction to vibration measurement. It discusses why vibration is measured, where vibration comes from, how to define and quantify vibration levels using parameters like acceleration, velocity, and displacement. It describes piezoelectric accelerometers, considerations for choosing measurement locations and parameters, and factors that influence accelerometer selection and accuracy like frequency range, mass, sensitivity, and resonance effects. The goal is to give newcomers to vibration measurement a brief overview of key concepts and equipment.
A strain gauge is a sensor that converts mechanical strain into resistance change. It consists of a thin metallic foil attached to the surface of an object. As the object is strained, the foil's resistance changes in proportion to the strain. This small resistance change is measured using a Wheatstone bridge circuit. The gauge factor is a measure of the sensor's sensitivity, relating the fractional resistance change to the fractional dimensional change caused by strain. Wireless strain sensors can operate for over 10 years without maintenance by using ultra-low power sensing and communication technologies.
The document discusses various types of transducers and their characteristics. It describes parameters like range, error, accuracy, resolution, sensitivity and hysteresis error. It also discusses stability, dead band, output impedance and dynamic characteristics like response time, time constant, rise time and settling time. Examples of different types of transducers are given, including resistive, capacitive, inductive, Hall effect, photoelectric and strain gauge transducers. Applications and limitations of each type are summarized.
This document discusses different types of displacement, position, and proximity sensors. It describes various contact and non-contact sensors such as potentiometers, strain gauges, LVDTs, capacitive sensors, Hall effect sensors, optical encoders, eddy current sensors, inductive sensors and microswitches. It provides details on their working principles, construction, applications in automation, metrology and other fields. Selection of appropriate sensors depends on factors like required accuracy, resolution, displacement size and cost.
The document discusses several common sensor types used for vibration measurements, including accelerometers, velocity sensors, proximity probes, and laser displacement sensors. Accelerometers use piezoelectric crystals to generate a charge proportional to acceleration. Velocity sensors induce a voltage in a coil moving through a magnetic field, proportional to velocity. Proximity probes measure displacement using capacitive or eddy current techniques. Laser displacement sensors use triangulation to determine position with high accuracy. Each sensor type has advantages and disadvantages for different vibration measurement applications.
This document provides an introduction to sensors and transducers. It defines a sensor as a device that receives and responds to a signal or stimulus, and a transducer as a device that converts one form of energy into another. The document then discusses different types of sensors classified by their energy form, including displacement, force, pressure, velocity, and level sensors. It provides examples of common sensor types like potentiometers, strain gauges, LVDTs, optical encoders, and piezoelectric sensors. Finally, it covers the topic of signal conditioning, where the signal from the sensor is prepared for use in other parts of a system.
The document discusses various specifications and characteristics of sensors, including:
1. Range is the maximum and minimum value range a sensor works well over. Accuracy is how well a sensor measures the environment compared to a standard. Resolution is a sensor's ability to see small differences in readings.
2. Drift is the low frequency change in a sensor over time. Hysteresis describes the difference between a sensor turning on and off. Response time is a sensor's frequency response.
3. Inductive proximity sensors generate an electromagnetic field and detect eddy current losses in metal targets. They have a typical hysteresis of 10% from the effective operating distance. Capacitive sensors generate an electrostatic field and react
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
TIME DIVISION MULTIPLEXING TECHNIQUE FOR COMMUNICATION SYSTEMHODECEDSIET
Time Division Multiplexing (TDM) is a method of transmitting multiple signals over a single communication channel by dividing the signal into many segments, each having a very short duration of time. These time slots are then allocated to different data streams, allowing multiple signals to share the same transmission medium efficiently. TDM is widely used in telecommunications and data communication systems.
### How TDM Works
1. **Time Slots Allocation**: The core principle of TDM is to assign distinct time slots to each signal. During each time slot, the respective signal is transmitted, and then the process repeats cyclically. For example, if there are four signals to be transmitted, the TDM cycle will divide time into four slots, each assigned to one signal.
2. **Synchronization**: Synchronization is crucial in TDM systems to ensure that the signals are correctly aligned with their respective time slots. Both the transmitter and receiver must be synchronized to avoid any overlap or loss of data. This synchronization is typically maintained by a clock signal that ensures time slots are accurately aligned.
3. **Frame Structure**: TDM data is organized into frames, where each frame consists of a set of time slots. Each frame is repeated at regular intervals, ensuring continuous transmission of data streams. The frame structure helps in managing the data streams and maintaining the synchronization between the transmitter and receiver.
4. **Multiplexer and Demultiplexer**: At the transmitting end, a multiplexer combines multiple input signals into a single composite signal by assigning each signal to a specific time slot. At the receiving end, a demultiplexer separates the composite signal back into individual signals based on their respective time slots.
### Types of TDM
1. **Synchronous TDM**: In synchronous TDM, time slots are pre-assigned to each signal, regardless of whether the signal has data to transmit or not. This can lead to inefficiencies if some time slots remain empty due to the absence of data.
2. **Asynchronous TDM (or Statistical TDM)**: Asynchronous TDM addresses the inefficiencies of synchronous TDM by allocating time slots dynamically based on the presence of data. Time slots are assigned only when there is data to transmit, which optimizes the use of the communication channel.
### Applications of TDM
- **Telecommunications**: TDM is extensively used in telecommunication systems, such as in T1 and E1 lines, where multiple telephone calls are transmitted over a single line by assigning each call to a specific time slot.
- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
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2. MEASUREMENT OF ACCELERATION, VIBRATION
AND DENSITY
Accelerometers: LVDT, Piezoelectric, Strain gauge and Variable reluctance type
accelerometers - Mechanical type vibration instruments - Seismic instruments as
accelerometer – Vibration sensor - Calibration of vibration pickups - Units of density and
specific gravity – Baume scale and API scale – Densitometers: Pressure type densitometers,
Float type densitometers, Ultrasonic densitometer and gas densitometer.
4. WORKING
A type of accelerometer takes advantage of the natural linear displacement measurement of the
LVDT to measure mass displacement.
LVDT is Linear Variable differential transducer which works on magnetic principle. In these
instruments, the LVDT core itself is the seismic mass.
Displacements of the core are converted directly into a linearly proportional ac voltage.
These accelerometers generally have a natural frequency less than 80 Hz and are commonly
used for steady-state and low-frequency vibration.
Fig. shows the basic structure of such an accelerometer.
5.
6.
7. EXPLANATION
The LVDT accelerometer consists of one primary and two secondary windings which are
placed on either side of central core.
The two ends of the core are connected with spring steel but these are already placed in a
casing.
If a core is exactly placed at the center, the voltage produced between primary and
secondary windings will be exactly equal; this voltage is called as static field voltage.
If any vibration occurs on the casings of the LVDT accelerometer, the core will either
move upward or downward.
Owing to this, the voltage is induced in the secondary coil according to the movement of
the core.
Now the difference in voltage arises in the output terminal.
This output voltage is directly proportional to the vibration or acceleration.
8. LVDT ACCELEROMETER
The linear Variable Differential Transformer (LVDT) described in pressure measurement section
offers another convenient means for measurement of the relatives displacement between the
seismic mass and accelerometer housing.
Such devices have somewhat higher natural frequencies than potentiometer devices (270 to 300
Hz) but are still restricted to applications with lower frequency response requirments.
The LVDT however has a much lower resistance to motion than the potentiometer and is capable
of much better resolution.
In addition, the seismic accelerometer using an LVDT can be considerably lighter in construction
than one with a potentiometer.
9.
10. ELECTRICAL RESISTANCE STRAIN GAUGE
The electrical resistance strain gauge discussed in earlier chapters may also be used for
displacement sensing in a seismic instrument.
Consider the schematic in fig. the seismic mass is mounted on a cantilever beam.
On each side of the beam a resistance strain gauge is mounted to sense the strain in the beam
resulting from the vibrational displacement of the mass.
Damping for the system is provided by the viscous liquid, which fulls the housing.
The outputs of the strain gauges are connected to an appropriate bridge circuit, which is used
to indicate the relative displacement between the mass and the housing frame.
The natural frequencies of such systems are fairly low and roughly comparable to that of the
LVDT systems.
11. Unbonded-strain-gauge accelerometers use the strain wires as the spring element
and as the motion tranducer.
They are useful for general-purpose motion measurement and for vibration up to
relatively high frequencies (17 to 800 hz)
12.
13. Bonded-strain gauge accelerometers generally use a mass supported by thin flexure beam,
wit strain gauges cemented to the beam so as to achieve maximum sensitivity, temperature
compensation, and insensitivity to cross-axis and angular acceleration.
Silicon-oil damping is widely used.
Semiconductor strain gauges (Piezoresistive sensors) are widely used as strain gauge
sensors in cantilever-beam/ mass types of accelerometers.
The semiconductor strain gauge type consists of semiconductors bonded to a mass whose
deformation under acceleration forces is reflected as a change of resistance.
The resistance measurement is made by means of a wheatstone bridge with the elements
16. The induced charge on the crystal is proportional to the impressed force and it is given by,
Q=dF
Where, Q=charge in coulombs
d = Piezoelectric constant
F = Force in Newtons
The output voltage of the crystal is given by E = gtp
Where
t = crystal thickness in meters
P = impressed pressure in Newtons/m2.
g=voltage sensitivity (g=d/ε)
19. The primary coils set up a flux dependent on the reluctance of the magnetic path. The main
reluctance is the air gap. When the core is in the neutral position, the flux is same for both
halves of the secondary coil; and since they are connected in series opposition, the net output
voltage is zero.
A motion of the core increases the reluctance (air gap) on one side and decreases it on the other,
causing more voltage to be induced into one half of the secondary coil than the other and thus a
net output voltage.
Motion in the other direction causes the reverse action, with a 180° phase shift occurring at
null. The output voltage is half wave, non-phase sensitive rectified (demodulated) and filtered
to produce an output of the same form as the acceleration input. If the 2.5 V output for zero-
acceleration is objectionable, it can be bucked out with a 2.5 V battery of opposite polarity
connected externally to the accelerometer.
The actual full-scale motion of the mass in this particular instrument is just a few thousandths
of 1m, which gives a displacement sensitivity for the variable-reluctance element of almost 500
V/cm.
20. EDDY CURRENT PROXIMITY
SENSOR AS VIBRATION PICK
UP
As the proximity detectors measure the distance between objects, they can be used to measure
frequencies and amplitude of vibrations.
To detect the proximity of conducting materials, an eddy current probe can be used.
The schematic arrangement of such a probe is shown in fig.
Two identical coils are wound on the probe, and these, together with the resistances, complete a
bridge circuit.
With no conducting surface near the probe, the bridge is in balance.
When a conducting object is brought near the probe, the bridge becomes unbalanced and the
output signal is in proportion to the proximity of the object.
21.
22. The excitation is a high frequency signal which induces eddy currents in the test
object.
The excitation is a high frequency signal which induces eddy currents in the test
object.
These currents produce losses in the bridge circuit in such a way that bridge
imbalance is related to the proximity of the object.
The output signal amplitude is related to the vibration or displacement amplitude,
and the frequency of vibration.
23. VIBRATION SENSOR
At present in the industry like research and development, the ability of monitoring,
measuring as well as analyzing the vibration is very important.
Unfortunately, the suitable techniques for making a measurement system for
vibration with precise & repeatable are not always clear to researchers with the
shades of test tools & analysis of vibration.
There are some challenges related while measuring the vibration which includes a
selection of suitable component, the configuration of the system, signal conditioning,
analysis of waveform and setup.
This article discusses what is a vibration sensor, working principle, types, and
applications
24. WHAT IS A VIBRATION SENSOR?
The vibration sensor is also called a piezoelectric sensor. These sensors are flexible
devices which are used for measuring various processes.
This sensor uses the piezoelectric effects while measuring the changes within
acceleration, pressure, temperature, force otherwise strain by changing to an
electrical charge.
This sensor is also used for deciding fragrances within the air by immediately
measuring capacitance as well as quality.
25. VIBRATION SENSOR WORKING
PRINCIPLE
The working principle of vibration sensor is a sensor which operates based on different
optical otherwise mechanical principles for detecting observed system vibrations.
The sensitivity of these sensors normally ranges from 10 mV/g to 100 mV/g, and there
are lower and higher sensitivities are also accessible. The sensitivity of the sensor can
be selected based on the application.
So it is essential to know the levels of vibration amplitude range to which the sensor will
be exposed throughout measurements.
26. VIBRATION SENSOR TYPES
The types of vibration sensors include the following.
Accelerometer Sensor
Strain Gauge Sensor
Velocity Sensor
Gyroscope Sensor
Pressure or Microphone Sensor
Laser Displacement Sensor
Capacitive Displacement or Eddy Current
Vibration Meter
Vibration Data Logger
27. The applications of vibration sensors include different industries for measuring the vibration. The exclusive
industrial characteristics will decide sensor characteristics.
For instance, this sensor is used in industries like wind power and mining for slow rotation of turbines with 1 Hz
or less frequency response.
In disparity, the industries like gas and oil need high frequency ranges from 10 Hz to 10 kHz uses these
sensors to handle with the speed rotation of gears and turbines.
The industries which use the vibration sensor mainly include food & beverage, mining, metalworking, gas & oil,
paper, wind power, power generation, etc.
Thus, this is all about vibration sensor. From the above information, finally, we can conclude that vibration is a
difficult measurement which includes different parameters. Based on the goals of vibration measurement, the
measurement technologies have benefits and drawbacks. These sensors are mainly used for measuring,
analyzing, displaying, proximity, acceleration, displacement, etc.
Applications
28. DENSITY
•Measurement of density becomes necessary in most industrial applications. Density measure
ments are done for all the three states of matter namely solids, liquids and gases.
•By measur ing the density of a process steam, one can determine its concentration composition,
or, in the case of fuels, its calorific value. Density measurements is also necessary to convert
volumetric flow measurements into mass flow information.
•For measuring the mass flow of gases, direct density measurement can be simpler and more
accurate than the indirect calculation which must consider pressure, temperature, super
compressibility, and humidity.
•The density of solids involves the weighing of a fixed volume. Density measurements are done
for slurry, viscous or clean process materials. Depending on the nature of the process media
(slurry, viscous, clean, solid, liquid, or gas etc.) densitometers are to be properly selected.
29. UNITS OF DENSITY, SPECIFIC
GRAVITY AND VISCOSITY
Density is defined as the quantity of matter per unit volume. Kg per cubic meter of any
object can be called as specific weight or 'weight density' of that object.
A second term known simply as 'density' is used to indicate the mass per cubic meter.
Though they refer to two entirely different things, in metric system of units, both are
interchangeably used as the weight of one kg mass is taken as one kgf. Kg is used as a unit
on many occasions for both mass and weight (or force), though Newton is the unit of
weight or force in metric units. (one kgf = 9.8 Newtons.)
30. RELATIVE DENSITY
Relative density, or specific gravity, is defined as the ratio between
the density of a process material to that of water or air at specified
conditions. Being a ratio, specific gravity has no units associated with
it. Water is used as reference for solid and liquid medias because of
its common occurrence.
31. Materials having specific gravities less than one are lighter than water, where as those having
specific gravities greater than one are heavier than water.
Both density and specific gravity characterise the same physical property of the process
media, and they are meaningful only if defined at stated temperatures.
In the case of specific gravity, the temperatures might be different for the process and the
reference fluid, which is acceptable, but must be clearly stated.
For example, a specific gravity table might list a process fluid as having 0.980/40 specific
gravity, which means that this liquid at 80°F will have a density of 0.9 times that of water at
40°F.
32. For Gases, the specific gravity is based on air at standard conditions (i.e, at STP-Stand ard temperature of 0°C and
pressure of 760 mmHg).
For ideal gases, the ratio of molecular weights equals specific gravity.Various Industrial Specific Gravity Scales.
The more common materials and liquids all have had their specific gravities determined entirely on the basis of
the ratio of their weights to the weight of an equal volume of water. (Similarly for gases with reference air).
But several specific gravity scales depart from this basis, and their values are not based on these simple ratios.
Some of the commonly used spe cific gravity units are defined below.
37. DISPLACEMENT AND FLOAT TYPE DENSITOMETERS
(FOR LIQUID DENSITY)
When an object of a fixed volume and a known density is submerged in a process fluid, the
resulting buoyant force can be detected as an indication of process density.
If the submerged float is lighter than the process fluid, the buoyant force will try to lift out
of the fluid and a force will be needed to keep the float submerged.
If the displacer is heavier than the process fluid, it will have a tendancy to sink and a force
will be required to hold it in position.
As the density of the process fluid increases, the apparent weight of the displacer will drop
38. CONVENTIONAL DISPLACER- TYPE
DENSITOMETER
Archimedes principle states that a body wholly or partially immersed in a fluid is buoyed up by a force
equal to the weight of the fluid displaced.
The sample fluid enters around the center section of the cage, through a piezometer ring which
eliminates the velocity effects of the flowing fluid.
For less velocity(<0.6 m/minutes) the piezometer ring is not essential.
The sample fluid leaves the case through the top and bottom connections.
It is recommended to keep these flows constant by the use of purgemeters.
The above system applies when the density measurement is made in a sample bypass of the process
piping.
If the density is to be measured in tanks or vessels, the flange mounted dsplacer illustrated below
41. SIDE MOUNTED DISPLACER
The sizing of the displacer has to be done taking the standard
force range of the displacer and the maximum and minimum
values of the density of process fluid into account.
42. CHAIN – BALANCED FLOAT
DENSITOMETER
The submerged float and chain assembly
displaces a fixed fluid volume.
Float buoyancy is a function of liquid density and
therefore an increase in density causes the float to
rise.
As it rises it will support a larger portion of the
calibrated chain, the weight of which cancels out
the increase in buoyancy so that a new equilibrium
condition is achieved.
The new float position is an indication of fluid
density.
45. The process fluid sample flows continuously through the detector at a constant rate. The
gauge chamber contains three displacer floats, each of different density and volume.
The solid displacers are spaced 90 to 100 degrees apart and assembled to a common shaft.
Each fluid density sample positions the shaft and displaces at a precise angular position.
The assembly rotation is a function of float position and buoyant force.
By having the three displacers moments in balance, the assembly is in equilibrium always.
The angular position of the assembly is transmitted to the electrical components through
magnetic coupling.
The output signal to remote readout devices is available in either analog or digital form.
46. HYDROMETERS
The hydrometer element consists of a weighted float with a small-diameter indicator stem
attachment at the top as shown in Fig. 4.33.
The stem is graduated in any of the density its discussed earlier.
According to Archimedes principle, when a body is immersed in a fluid it loses its weight equal
to the weight of the liquid which is displaced.
The hydrometer element is a constant-weight body which, if immersed in fluid with differing
densites, will displace differing volumes of fluid.
Therefore, the degree of stem scale submersion is an indication of fluid density.
Readings are made at the point where the stem emerges from the liquid.
One of the simplest in-line density indicators is illustrated in Fig. 4.34.
It consists of a transparent glass tee with a hydrometer element. The process fluid enters from
bottom and overflows to maintain constant level in the tee.
A thermometer is added for temperature correction purpose.