Study on impedance variable type semiconductor gas sensor
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Metal-oxide semiconductor gas sensors are effective to air environment monitoring and indoor gas leakage detection, etc., because of the high sensitivity property.
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Temperature Sensors
The document discusses several common types of temperature sensors, including thermocouples, thermistors, resistance temperature detectors (RTDs), liquid in glass thermometers, and bimetallic sensors. It provides details on the basic operating principles, advantages, disadvantages and applications of each sensor type. Thermocouples measure temperature differences using dissimilar metals and the Seebeck effect. Thermistors have a resistance that varies with temperature. RTDs use platinum wire whose resistance changes predictably with temperature. Liquid in glass thermometers use expansion of liquid along a glass tube. Bimetallic sensors use strips of two metals with different expansion rates.
Thermistor
Thermistors are non-metallic resistors made of ceramic materials that have a negative coefficient of resistance. Their resistance decreases as temperature increases, allowing them to be used for precise temperature measurement. A thermistor has a ceramic sensing element housed inside a metal tube, with lead wires connecting it to a Wheatstone bridge circuit. As temperature rises, the sensing element's decreasing resistance is measured to calculate the temperature change. Thermistors are widely used for temperature compensation, time delay circuits, and measuring thermal conductivity or fluid properties due to their low cost, high accuracy, and ability to withstand stresses.
Rtd
Resistance temperature detectors (RTDs) measure temperature changes by detecting corresponding changes in electrical resistance of a conductor. Platinum is commonly used as the conductor. When temperature increases, the conductor expands, altering its electrical resistance. RTDs have a sensing element connected by leads to a Wheatstone bridge circuit. A constant current is passed through the sensing element, and its changing resistance is measured by the bridge to determine the temperature. RTDs provide accurate, reproducible temperature measurements for remote or continuous monitoring applications. Their main limitation is slower response time due to protective casings around the sensing element.
Thermocouple
Thermocouples produce a voltage related to temperature difference based on the Seebeck effect. Common materials used include chromel-alumel for Type K and iron-constantan for Type J. Thermocouples have advantages such as wide temperature range, long transmission distances, low cost, and fast response time. Limitations include needing cold junction compensation and signal amplification. Applications include temperature monitoring in steel making and heating appliances.
Introduction to rtd and thermocouple by yogesh k. kirange
Transducers convert one form of energy into another. There are two main types of transducers - active and passive. Transducers can also be classified based on their output type (analog or digital) or the electrical principle involved. Resistance temperature detectors (RTDs) and thermocouples are common temperature measurement transducers. RTDs use platinum resistors whose resistance changes predictably with temperature. Thermocouples produce voltage when two dissimilar metals are joined at both ends and one end is heated. Common thermocouple types include J, K, and T.
Thermocouple as a Transducer ppt
This document discusses thermocouples as temperature transducers. It begins with an introduction to thermocouples, explaining that they use the Seebeck effect to produce voltage when two different metals are joined and experience a temperature difference. The document then covers the definition, working principles including Seebeck, Peltier and Thompson effects, construction including junction types, working, measurement of output, advantages including low cost and fast response, disadvantages like low accuracy, and applications such as in thermostats, metal industries, food industries, and chemical plants. In summary, the document provides an overview of thermocouples as temperature sensors that operate based on the Seebeck effect and are used across various industrial and commercial applications.
Rtd and thermocouples
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.
Thermocouple- Metrology& Instrumentation
The thermocouple is a device which converts thermal energy to electrical energy. It is particularly used as a thermosensor. It has wider applications in instrumentation and measurements.
This PPT gathered many relevant topics relating to thermocouple like its working, principle, laws and different types.
Thank you!
Recommended
Temperature Sensors
The document discusses several common types of temperature sensors, including thermocouples, thermistors, resistance temperature detectors (RTDs), liquid in glass thermometers, and bimetallic sensors. It provides details on the basic operating principles, advantages, disadvantages and applications of each sensor type. Thermocouples measure temperature differences using dissimilar metals and the Seebeck effect. Thermistors have a resistance that varies with temperature. RTDs use platinum wire whose resistance changes predictably with temperature. Liquid in glass thermometers use expansion of liquid along a glass tube. Bimetallic sensors use strips of two metals with different expansion rates.
Thermistor
Thermistors are non-metallic resistors made of ceramic materials that have a negative coefficient of resistance. Their resistance decreases as temperature increases, allowing them to be used for precise temperature measurement. A thermistor has a ceramic sensing element housed inside a metal tube, with lead wires connecting it to a Wheatstone bridge circuit. As temperature rises, the sensing element's decreasing resistance is measured to calculate the temperature change. Thermistors are widely used for temperature compensation, time delay circuits, and measuring thermal conductivity or fluid properties due to their low cost, high accuracy, and ability to withstand stresses.
Rtd
Resistance temperature detectors (RTDs) measure temperature changes by detecting corresponding changes in electrical resistance of a conductor. Platinum is commonly used as the conductor. When temperature increases, the conductor expands, altering its electrical resistance. RTDs have a sensing element connected by leads to a Wheatstone bridge circuit. A constant current is passed through the sensing element, and its changing resistance is measured by the bridge to determine the temperature. RTDs provide accurate, reproducible temperature measurements for remote or continuous monitoring applications. Their main limitation is slower response time due to protective casings around the sensing element.
Thermocouple
Thermocouples produce a voltage related to temperature difference based on the Seebeck effect. Common materials used include chromel-alumel for Type K and iron-constantan for Type J. Thermocouples have advantages such as wide temperature range, long transmission distances, low cost, and fast response time. Limitations include needing cold junction compensation and signal amplification. Applications include temperature monitoring in steel making and heating appliances.
Introduction to rtd and thermocouple by yogesh k. kirange
Transducers convert one form of energy into another. There are two main types of transducers - active and passive. Transducers can also be classified based on their output type (analog or digital) or the electrical principle involved. Resistance temperature detectors (RTDs) and thermocouples are common temperature measurement transducers. RTDs use platinum resistors whose resistance changes predictably with temperature. Thermocouples produce voltage when two dissimilar metals are joined at both ends and one end is heated. Common thermocouple types include J, K, and T.
Thermocouple as a Transducer ppt
This document discusses thermocouples as temperature transducers. It begins with an introduction to thermocouples, explaining that they use the Seebeck effect to produce voltage when two different metals are joined and experience a temperature difference. The document then covers the definition, working principles including Seebeck, Peltier and Thompson effects, construction including junction types, working, measurement of output, advantages including low cost and fast response, disadvantages like low accuracy, and applications such as in thermostats, metal industries, food industries, and chemical plants. In summary, the document provides an overview of thermocouples as temperature sensors that operate based on the Seebeck effect and are used across various industrial and commercial applications.
Rtd and thermocouples
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.
Thermocouple- Metrology& Instrumentation
The thermocouple is a device which converts thermal energy to electrical energy. It is particularly used as a thermosensor. It has wider applications in instrumentation and measurements.
This PPT gathered many relevant topics relating to thermocouple like its working, principle, laws and different types.
Thank you!
Thermocouple sensor
Thermocouples are temperature sensors consisting of two dissimilar metals joined together at two junctions. One junction, the measuring or hot junction, is connected to the body whose temperature is being measured. The other junction, the reference or cold junction, is connected to a body of known temperature. A temperature difference between the junctions produces an electric voltage due to the Seebeck effect. Thermocouples are widely used to measure temperature in industrial processes like furnaces and engines as well as in thermostats and fire alarms.
RTD-RESISTANCE TEMPERATURE DETECTOR
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.
Temperature Transducer
The document discusses different types of temperature transducers, focusing on thermocouples and RTDs. It provides details on how thermocouples and RTDs function to measure temperature, their common applications, advantages and disadvantages.
Specifically, it explains that thermocouples use the Seebeck effect to generate voltage based on a junction of two dissimilar metals, while RTDs measure the change in resistance of materials like platinum as their temperature varies. It also lists standard thermocouple types and common resistance materials used for RTDs, as well as different forms that RTDs can take like probes.
Thermocouple as a Transducer
Thermocouples are transducers that convert heat directly into electricity according to the Seebeck effect. They consist of two conductors welded together at one end to form a junction, with the voltage difference between the junctions proportional to the temperature difference. The main types are K, J, T, E, N, S, B, and R, which differ in temperature range and sensitivity. Thermocouples are used to measure temperature and generate power due to their ruggedness, low cost, and ability to function over a wide range of temperatures. However, they also have low accuracy and can be vulnerable to corrosion.
thermocouple ppt
Thermocouples are temperature measurement devices that produce a voltage when two different conductors contact each other at different temperatures. The voltage is proportional to the temperature difference and relies on the Seebeck effect where a temperature gradient along conductors generates an electric current. Common thermocouple types use different metal combinations like chromel-iron and alumel-constantan wired into a circuit to measure temperature in various applications such as steel production, gas appliances, and vacuum gauges.
Thermistor
Thermistors are a type of resistor whose resistance changes significantly with temperature. They are made of semiconducting materials like metal oxides and their resistance decreases with rising temperature (NTC thermistors) or increases with rising temperature (PTC thermistors). NTC thermistors are used in applications like temperature sensors and overcurrent protection, while PTC thermistors are used in self-regulating heaters and current-limiting devices. Thermistors have a fast response time, are compact and inexpensive but have non-linear resistance-temperature characteristics and may self-heat.
Circuit labthermistors (1)
The document discusses a student project to develop a temperature control system using a thermistor. The thermistor is a negative temperature coefficient sensor whose resistance decreases with increasing temperature. The project involves taking resistance measurements of the thermistor at different water bath temperatures in order to characterize its temperature-resistance relationship. An operational amplifier circuit will be used to actuate a relay and switch on a lamp if the temperature rises above a certain threshold, indicating the temperature control system is working automatically. The goal is to obtain hands-on knowledge of temperature control using a thermistor and demonstrate its applications in engineering fields.
Rtd (resistance temperature detector)
This document discusses resistance temperature detectors (RTDs). It begins by explaining that RTDs measure temperature by measuring the resistance of the sensing element, which increases proportionally with temperature. It then lists common uses of RTDs, which include when accuracy is important, over a wide temperature range, or for area sensing. The document goes on to describe common components of RTDs like the platinum sensing element. It discusses different types of sensing elements, wiring configurations, advantages and disadvantages, and applications.
THERMOELECTRIC COOLER
Thermoelectric cooling uses the Peltier effect to create a heat flux between the junction of two different types of materials.
Thermocouple
Thermocouples are temperature sensors that use the Seebeck effect to measure temperature by generating a voltage proportional to the temperature difference between the thermocouple junction and a reference junction. They consist of two dissimilar metals welded together at the measuring junction. Common types include K, J, T, E, which have different temperature ranges and sensitivities. Thermocouples are widely used to measure temperature in industrial processes, kilns, engines, and other applications requiring temperature measurement.
Thermoelectic Cooling Module
This document summarizes a seminar presentation on thermoelectric cooling systems. It introduces thermoelectric coolers and their basic principles, including the Peltier effect whereby applying a voltage creates a heat pump effect. Common materials used are bismuth telluride semiconductors. Multistage cooler designs can improve performance by decreasing the minimum cold side temperature. Thermoelectric coolers have advantages over vapor compression systems like no moving parts, quick response time, and lower power usage. Applications include electronics cooling, refrigeration, medical and laboratory equipment.
thermometric refrigeration system
This document presents a thermoelectric refrigeration system project. It discusses the milestones, realization of the idea, introduction to thermoelectric refrigeration and the Peltier effect. It describes the materials used, working of the project including dimensions, advantages, drawbacks, applications, cost analysis, new opportunities, and concludes that the objective of long term cooling in power failures was achieved with a retention time of 57 minutes.
Seebeck effect & peltier effect
The document summarizes the Seebeck effect and Peltier effect.
The Seebeck effect describes how a temperature difference across two dissimilar metals or semiconductors generates an electric current. The Peltier effect is the reverse, where an electric current generates a heat difference at the junction between two materials.
Both effects are reversible and form the basis for thermoelectric devices. The Seebeck effect enables applications like thermoelectric generators and thermocouples for temperature measurement. The Peltier effect allows for solid-state refrigeration in devices with no moving parts like Peltier coolers.
Thermoelectric cooler
The document discusses thermoelectric cooling, which uses the Peltier effect to create a heat pump-like cooling system without moving parts. It operates by passing a current through two dissimilar conductors joined at two points maintained at different temperatures. When current is applied, heat is absorbed at one junction and expelled at the other, allowing one side to be cooled. Thermoelectric coolers use semiconductors like bismuth telluride in a series of p-n junctions to transfer heat from one side to the other in response to an applied current, providing solid-state cooling without liquids or gases.
Resistance thermometer circuit
The document describes the construction and working of a resistance thermometer, which uses a Wheatstone bridge circuit to measure the changing resistance of a thermometer bulb in contact with an object to determine its temperature. Key components include a battery, galvanometer, thermometer bulb, fixed resistors A and B, and an adjustable slide wire resistor s. The resistance of the bulb r is determined through balancing the Wheatstone bridge and calculating the ratio of r to the portion of s in the circuit. Improved versions address issues like contact resistance affecting measurements.
Thermocouple by Engr. Imran Tanvir
A thermocouple is a device that uses the Seebeck effect to convert temperature differences into electrical signals. It consists of two dissimilar metals joined together at two points called thermocouple junctions. When the junctions are at different temperatures, it generates a voltage that can be measured to determine the unknown temperature. Common types of thermocouples use combinations like copper-constantan, iron-constantan, and chromel-alumel wires. Thermocouples have a wide temperature range but lower accuracy compared to resistance temperature detectors. They are cheaper, respond faster, and are well suited for applications that require temperature measurements over a broad range.
Thermocouple
A Thermocouple is a sensor used to measure temperature. Thermocouples consist of two wire legs made from different metals. The wires legs are welded together at one end, creating a junction. This junction is where the temperature is measured. When the junction experiences a change in temperature, a voltage is created. The voltage can then be interpreted using thermocouple reference tables to calculate the temperature.
There are many types of thermocouples, each with its own unique characteristics in terms of temperature range, durability, vibration resistance, chemical resistance, and application compatibility. Type J, K, T, & E are “Base Metal” thermocouples, the most common types of thermocouples.Type R, S, and B thermocouples are “Noble Metal” thermocouples, which are used in high temperature applications (see thermocouple temperature ranges for details).
Thermocouples are used in many industrial, scientific, and OEM applications. They can be found in nearly all industrial markets: Power Generation, Oil/Gas, Pharmaceutical, Bio Tech, Cement, Paper & Pulp, etc. Thermocouples are also used in everyday appliances like stoves, furnaces, and toasters.
Thermocouples are typically selected because of their low cost, high temperature limits, wide temperature ranges, and durable nature.
Ppt final
In 1821, Seebeck discovered that a temperature difference across two dissimilar conductors produces a voltage. Good thermoelectric materials have a large Seebeck coefficient and high electrical conductivity with low thermal conductivity, such as bismuth telluride. A thermoelectric generator uses p-type and n-type semiconductors packed between hot and cold side plates to produce electricity from a temperature difference based on the Seebeck effect. The proposed work will fabricate a thermoelectric generator module and test it using a heat source and measuring the voltage and current output at different temperatures.
Thermocouples
Thermocouples operate by generating a voltage when two dissimilar metals are joined and exposed to different temperatures. They are inexpensive, small, and accurate when used properly. Thermocouples work based on the Seebeck effect where a voltage is produced due to temperature differences between junctions. Tables are used to correlate the voltage measured to a specific temperature once the reference junction temperature is accounted for through laws such as the Law of Intermediate Temperatures. Common thermocouple types are T, J, and K, with the material chosen based on the required temperature range and accuracy.
Indirect Power Saving From Air Conditioner
Indirect Power Saving From Air Conditioner is a project on regenerating energy from the waste heat of the air conditioner or you could say electrical energy waste management. The output we received is not so efficient but can be improved in further research. All types of suggestions critics are welcome. The thesis of the project link https://www.slideshare.net/SandipKumarSahoo/indirect-power-saving-from-air-conditioner-thesis
fan speed control by using temperature sensor
This document describes a fan control circuit that uses a temperature sensor. The circuit uses a thermistor temperature sensor that varies resistance based on temperature to control the speed of a DC fan. As temperature increases, fan speed increases to cool the area. The circuit aims to reduce power consumption by only running the fan as needed based on temperature. It could assist disabled individuals and be used for temperature monitoring and control in various industries.
Sensors and transducers Working,Applications
The document discusses various types of sensors and transducers, including how they work. It describes infrared (IR) sensors, photodiodes, light dependent resistors (LDRs), thermistors, thermocouples, strain gauges, load cells, potentiometers, encoders, Hall sensors, flex sensors, microphones, and ultrasonic sensors. For each sensor, it provides details on the basic components, working principles, and some common applications.
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Thermocouple sensor
Thermocouples are temperature sensors consisting of two dissimilar metals joined together at two junctions. One junction, the measuring or hot junction, is connected to the body whose temperature is being measured. The other junction, the reference or cold junction, is connected to a body of known temperature. A temperature difference between the junctions produces an electric voltage due to the Seebeck effect. Thermocouples are widely used to measure temperature in industrial processes like furnaces and engines as well as in thermostats and fire alarms.
RTD-RESISTANCE TEMPERATURE DETECTOR
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.
Temperature Transducer
The document discusses different types of temperature transducers, focusing on thermocouples and RTDs. It provides details on how thermocouples and RTDs function to measure temperature, their common applications, advantages and disadvantages.
Specifically, it explains that thermocouples use the Seebeck effect to generate voltage based on a junction of two dissimilar metals, while RTDs measure the change in resistance of materials like platinum as their temperature varies. It also lists standard thermocouple types and common resistance materials used for RTDs, as well as different forms that RTDs can take like probes.
Thermocouple as a Transducer
Thermocouples are transducers that convert heat directly into electricity according to the Seebeck effect. They consist of two conductors welded together at one end to form a junction, with the voltage difference between the junctions proportional to the temperature difference. The main types are K, J, T, E, N, S, B, and R, which differ in temperature range and sensitivity. Thermocouples are used to measure temperature and generate power due to their ruggedness, low cost, and ability to function over a wide range of temperatures. However, they also have low accuracy and can be vulnerable to corrosion.
thermocouple ppt
Thermocouples are temperature measurement devices that produce a voltage when two different conductors contact each other at different temperatures. The voltage is proportional to the temperature difference and relies on the Seebeck effect where a temperature gradient along conductors generates an electric current. Common thermocouple types use different metal combinations like chromel-iron and alumel-constantan wired into a circuit to measure temperature in various applications such as steel production, gas appliances, and vacuum gauges.
Thermistor
Thermistors are a type of resistor whose resistance changes significantly with temperature. They are made of semiconducting materials like metal oxides and their resistance decreases with rising temperature (NTC thermistors) or increases with rising temperature (PTC thermistors). NTC thermistors are used in applications like temperature sensors and overcurrent protection, while PTC thermistors are used in self-regulating heaters and current-limiting devices. Thermistors have a fast response time, are compact and inexpensive but have non-linear resistance-temperature characteristics and may self-heat.
Circuit labthermistors (1)
The document discusses a student project to develop a temperature control system using a thermistor. The thermistor is a negative temperature coefficient sensor whose resistance decreases with increasing temperature. The project involves taking resistance measurements of the thermistor at different water bath temperatures in order to characterize its temperature-resistance relationship. An operational amplifier circuit will be used to actuate a relay and switch on a lamp if the temperature rises above a certain threshold, indicating the temperature control system is working automatically. The goal is to obtain hands-on knowledge of temperature control using a thermistor and demonstrate its applications in engineering fields.
Rtd (resistance temperature detector)
This document discusses resistance temperature detectors (RTDs). It begins by explaining that RTDs measure temperature by measuring the resistance of the sensing element, which increases proportionally with temperature. It then lists common uses of RTDs, which include when accuracy is important, over a wide temperature range, or for area sensing. The document goes on to describe common components of RTDs like the platinum sensing element. It discusses different types of sensing elements, wiring configurations, advantages and disadvantages, and applications.
THERMOELECTRIC COOLER
Thermoelectric cooling uses the Peltier effect to create a heat flux between the junction of two different types of materials.
Thermocouple
Thermocouples are temperature sensors that use the Seebeck effect to measure temperature by generating a voltage proportional to the temperature difference between the thermocouple junction and a reference junction. They consist of two dissimilar metals welded together at the measuring junction. Common types include K, J, T, E, which have different temperature ranges and sensitivities. Thermocouples are widely used to measure temperature in industrial processes, kilns, engines, and other applications requiring temperature measurement.
Thermoelectic Cooling Module
This document summarizes a seminar presentation on thermoelectric cooling systems. It introduces thermoelectric coolers and their basic principles, including the Peltier effect whereby applying a voltage creates a heat pump effect. Common materials used are bismuth telluride semiconductors. Multistage cooler designs can improve performance by decreasing the minimum cold side temperature. Thermoelectric coolers have advantages over vapor compression systems like no moving parts, quick response time, and lower power usage. Applications include electronics cooling, refrigeration, medical and laboratory equipment.
thermometric refrigeration system
This document presents a thermoelectric refrigeration system project. It discusses the milestones, realization of the idea, introduction to thermoelectric refrigeration and the Peltier effect. It describes the materials used, working of the project including dimensions, advantages, drawbacks, applications, cost analysis, new opportunities, and concludes that the objective of long term cooling in power failures was achieved with a retention time of 57 minutes.
Seebeck effect & peltier effect
The document summarizes the Seebeck effect and Peltier effect.
The Seebeck effect describes how a temperature difference across two dissimilar metals or semiconductors generates an electric current. The Peltier effect is the reverse, where an electric current generates a heat difference at the junction between two materials.
Both effects are reversible and form the basis for thermoelectric devices. The Seebeck effect enables applications like thermoelectric generators and thermocouples for temperature measurement. The Peltier effect allows for solid-state refrigeration in devices with no moving parts like Peltier coolers.
Thermoelectric cooler
The document discusses thermoelectric cooling, which uses the Peltier effect to create a heat pump-like cooling system without moving parts. It operates by passing a current through two dissimilar conductors joined at two points maintained at different temperatures. When current is applied, heat is absorbed at one junction and expelled at the other, allowing one side to be cooled. Thermoelectric coolers use semiconductors like bismuth telluride in a series of p-n junctions to transfer heat from one side to the other in response to an applied current, providing solid-state cooling without liquids or gases.
Resistance thermometer circuit
The document describes the construction and working of a resistance thermometer, which uses a Wheatstone bridge circuit to measure the changing resistance of a thermometer bulb in contact with an object to determine its temperature. Key components include a battery, galvanometer, thermometer bulb, fixed resistors A and B, and an adjustable slide wire resistor s. The resistance of the bulb r is determined through balancing the Wheatstone bridge and calculating the ratio of r to the portion of s in the circuit. Improved versions address issues like contact resistance affecting measurements.
Thermocouple by Engr. Imran Tanvir
A thermocouple is a device that uses the Seebeck effect to convert temperature differences into electrical signals. It consists of two dissimilar metals joined together at two points called thermocouple junctions. When the junctions are at different temperatures, it generates a voltage that can be measured to determine the unknown temperature. Common types of thermocouples use combinations like copper-constantan, iron-constantan, and chromel-alumel wires. Thermocouples have a wide temperature range but lower accuracy compared to resistance temperature detectors. They are cheaper, respond faster, and are well suited for applications that require temperature measurements over a broad range.
Thermocouple
A Thermocouple is a sensor used to measure temperature. Thermocouples consist of two wire legs made from different metals. The wires legs are welded together at one end, creating a junction. This junction is where the temperature is measured. When the junction experiences a change in temperature, a voltage is created. The voltage can then be interpreted using thermocouple reference tables to calculate the temperature.
There are many types of thermocouples, each with its own unique characteristics in terms of temperature range, durability, vibration resistance, chemical resistance, and application compatibility. Type J, K, T, & E are “Base Metal” thermocouples, the most common types of thermocouples.Type R, S, and B thermocouples are “Noble Metal” thermocouples, which are used in high temperature applications (see thermocouple temperature ranges for details).
Thermocouples are used in many industrial, scientific, and OEM applications. They can be found in nearly all industrial markets: Power Generation, Oil/Gas, Pharmaceutical, Bio Tech, Cement, Paper & Pulp, etc. Thermocouples are also used in everyday appliances like stoves, furnaces, and toasters.
Thermocouples are typically selected because of their low cost, high temperature limits, wide temperature ranges, and durable nature.
Ppt final
In 1821, Seebeck discovered that a temperature difference across two dissimilar conductors produces a voltage. Good thermoelectric materials have a large Seebeck coefficient and high electrical conductivity with low thermal conductivity, such as bismuth telluride. A thermoelectric generator uses p-type and n-type semiconductors packed between hot and cold side plates to produce electricity from a temperature difference based on the Seebeck effect. The proposed work will fabricate a thermoelectric generator module and test it using a heat source and measuring the voltage and current output at different temperatures.
Thermocouples
Thermocouples operate by generating a voltage when two dissimilar metals are joined and exposed to different temperatures. They are inexpensive, small, and accurate when used properly. Thermocouples work based on the Seebeck effect where a voltage is produced due to temperature differences between junctions. Tables are used to correlate the voltage measured to a specific temperature once the reference junction temperature is accounted for through laws such as the Law of Intermediate Temperatures. Common thermocouple types are T, J, and K, with the material chosen based on the required temperature range and accuracy.
Indirect Power Saving From Air Conditioner
Indirect Power Saving From Air Conditioner is a project on regenerating energy from the waste heat of the air conditioner or you could say electrical energy waste management. The output we received is not so efficient but can be improved in further research. All types of suggestions critics are welcome. The thesis of the project link https://www.slideshare.net/SandipKumarSahoo/indirect-power-saving-from-air-conditioner-thesis
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Similar to Study on impedance variable type semiconductor gas sensor
fan speed control by using temperature sensor
This document describes a fan control circuit that uses a temperature sensor. The circuit uses a thermistor temperature sensor that varies resistance based on temperature to control the speed of a DC fan. As temperature increases, fan speed increases to cool the area. The circuit aims to reduce power consumption by only running the fan as needed based on temperature. It could assist disabled individuals and be used for temperature monitoring and control in various industries.
Sensors and transducers Working,Applications
The document discusses various types of sensors and transducers, including how they work. It describes infrared (IR) sensors, photodiodes, light dependent resistors (LDRs), thermistors, thermocouples, strain gauges, load cells, potentiometers, encoders, Hall sensors, flex sensors, microphones, and ultrasonic sensors. For each sensor, it provides details on the basic components, working principles, and some common applications.
Sensors
This document discusses various common sensors and measurement techniques used in oceanography and industrial processes. It describes temperature sensors like RTDs, thermocouples, and thermistors. It also covers pressure sensors such as diaphragm, piezoelectric, and bourdon tube sensors. Level measurement techniques discussed include gauge glass, probe, dip tube, radar, and ultrasonic sensors. Flow measurement includes turbine, electromagnetic, ultrasonic, and doppler flow meters. Other sensors covered are salinometers, viscorators, and smoke detectors.
Unit ii sensors and actuators
The document discusses various automotive sensors and actuators. It provides details on Hall effect, thermistor, piezoelectric and other common sensor types used in vehicles. It describes sensors for measuring oxygen concentration, air flow, manifold pressure, throttle position, oil pressure, vehicle speed and more. Actuators discussed include stepper motors, relays, and how solenoids are used for fuel injectors and EGR valves to regulate gas flow. The principles and applications of different sensor technologies like resistive, optical, and piezoelectric sensors are also summarized.
A presentation on transducerpptx
The document discusses transducers and strain gauges. It defines a transducer as a device that converts one form of energy to another, providing examples like microphones and thermometers. It describes strain gauges, which measure strain or deformation, working by changing electrical resistance when force is applied. Strain gauges are used to measure pressure, force, weight and tension. The document also explains how strain gauges work using foil resistance grids and a Wheatstone bridge circuit to detect small resistance changes.
Transducers and data acquisition systems
This document discusses transducers and data acquisition systems. It covers several types of transducers including resistive, capacitive, inductive, piezoelectric, optical and digital transducers. It also discusses how transducers are classified and selected. The document then covers data acquisition systems, explaining that they convert real-world signals to digital values. A data acquisition system typically includes transducers, signal conditioning hardware, and an interface to a computer for processing.
Physical Effects for sensors
A sensor is a transducer whose purpose is to sense (that is, to detect) some characteristic of its environs. It detects events or changes in quantities and provides a corresponding output, generally as an electrical or optical signal; for example, a thermocouple converts temperature to an output voltage. But a mercury-in-glass thermometer is also a sensor; it converts the measured temperature into expansion and contraction of a liquid which can be read on a calibrated glass tube.
Sensors are used in everyday objects such as touch-sensitive elevator buttons (tactile sensor) and lamps which dim or brighten by touching the base, besides innumerable applications of which most people are never aware. With advances in micromachinery and easy-to-use microcontroller platforms, the uses of sensors have expanded beyond the more traditional fields of temperature, pressure or flow measurement. Moreover, analog sensors such as potentiometers and force-sensing resistors are still widely used. Applications include manufacturing and machinery, airplanes and aerospace, cars, medicine and robotics.
A sensor's sensitivity indicates how much the sensor's output changes when the input quantity being measured changes. Some sensors can also have an impact on what they measure; for instance, a room temperature thermometer inserted into a hot cup of liquid cools the liquid while the liquid heats the thermometer. Sensors need to be designed to have a small effect on what is measured; making the sensor smaller often improves this and may introduce other advantages. Technological progress allows more and more sensors to be manufactured on a microscopic scale as microsensors using MEMS technology. In most cases, a microsensor reaches a significantly higher speed and sensitivity compared with macroscopic approaches.
The sensitivity is then defined as the ratio between output signal and measured property. For example, if a sensor measures temperature and has a voltage output, the sensitivity is a constant with the unit [V/K]; this sensor is linear because the ratio is constant at all points of measurement. For an analog sensor signal to be processed, or used in digital equipment, it needs to be converted to a digital signal, using an analog-to-digital converter.
Electromagnetic and mechanical sensors
1. The document discusses various types of sensors including electromagnetic sensors, mechanical sensors, and gas sensors. It provides details on common sensors like resistance sensors, current sensors, voltage sensors, and pressure sensors.
2. Examples of applications mentioned include uses in automobiles, industry, medicine, aerospace, process control, environmental monitoring, and more.
3. The operating principles of different sensors are explained, such as how resistance sensors measure resistance, current sensors detect current, and pressure sensors convert pressure into electrical signals.
Introduction to transducers
Definition, classification, selection of transducer.
Measurement of temperature: using R T D, thermocouple,
bimetallic thermometer, Pressure thermometers, pyrometers.
Pressure Measurement: Bourdon Tubes, bellows, diaphragms
Vacuum Measurement: McLeod gauge, pirani gauge
voltammetry basics.pptx
This document discusses various electrochemical techniques including voltammetry and polarography. It describes how voltammetry works by plotting current as a function of applied potential. Polarography uses a mercury working electrode. Different electrode configurations (e.g. solid vs. dropping mercury electrode) and cell designs (e.g. 2-electrode vs. 3-electrode) are discussed. Various factors that influence the measurements including mass transport and potential excitations are also summarized.
IOT SENSORS
This document discusses different types of sensors used in IoT applications. It describes resistive sensors like potentiometers, photoresistors, and thermistors. It also covers temperature sensors like thermocouples and RTDs. Other sensor types discussed include strain gauges, capacitive sensors, ultrasonic sensors, and MEMS sensors. For each sensor type, the document provides details on working principles, examples, and applications.
Resistors: Types and Uses
A resistor is a passive electronic component that limits current or reduces voltage in a circuit. There are several types of resistors including fixed resistors, variable resistors like potentiometers and rheostats, and resistors with properties dependent on other factors like temperature (thermistors), light (LDRs), and voltage (varistors). Variable resistors allow changing the resistance as needed in a circuit and are used for applications like calibration.
Basic transducer principles
The working of diffrent transducers and its priciples are discussed. The various types of sensors, transducers for the biopotential detections are also discussed with necessary diagrams.
Advanced Sensors
This document discusses several types of advanced sensors. It begins by distinguishing between analog and digital sensors, with analog sensors producing continuous outputs and digital sensors producing discrete outputs. It then examines several specific sensor types in more detail, including position sensors like potentiometers; temperature sensors like thermostats and thermocouples; light sensors such as photoresistors; and motion sensors including passive infrared and ultrasonic sensors. The document concludes by noting the wide variety of advanced sensors that can perform different functions.
Working Principals of Various Sensors
A light sensor detects ambient light levels and can include photoresistors, photodiodes, or phototransistors. It works by measuring changes in electrical resistance, voltage, or current caused by exposure to light. Light sensors have a wide range of applications including in street lights, cameras, alarms, and automatic lighting controls.
Types and functions of sensors
The sensor is a new high-tech technology used to measure physical and chemical effects. It has a wide range of applications in life.
Transducers
This document discusses transducers, which are devices that convert one form of energy into another. It describes various types of transducers such as temperature, displacement, and resistance transducers. Transducers are classified based on the transduction form used, whether they are primary or secondary, passive or active, analog or digital. Key factors in selecting a transducer include operating principle, sensitivity, range, accuracy, and environmental compatibility. The basic construction of a transducer includes a sensing element that responds to changes and a transduction element that converts this to an electrical signal. Transducers have applications in equipment like audio/video and advantages like remote output and electrical amplification.
Deep explanation of gas sensors for engineering students
The document discusses gas sensors. It begins by defining a sensor and listing common sensor applications. It then defines gas sensors as a subclass of chemical sensors that measure the concentration of gas. Various gas sensing technologies are described, including metal oxide, capacitive, acoustic, calorimetric, optical, and electrochemical sensors. Metal oxide sensors detect gas concentration changes by measuring resistance changes of a thin film. Capacitive sensors measure dielectric constant changes. Acoustic sensors use piezoelectric materials. Calorimetric sensors detect heat changes from gas combustion. Optical sensors use techniques like ellipsometry and spectroscopy. Electrochemical sensors create current from gas oxidation and reduction reactions. Applications and advantages of gas sensors
components.pptx good for used components
The document provides information about several different sensors:
- Ultrasonic sensors transmit ultrasonic waves and detect their reflection to measure distance. The HC-SR04 module can measure distances from 2-200 cm.
- Infrared sensors detect infrared light for proximity detection. They have an IR LED transmitter and photodiode receiver.
- LDR sensors have a resistance that decreases with increasing light intensity, allowing them to be used in light-sensing circuits.
- The DHT11 sensor measures both temperature and humidity using a thermistor and capacitive humidity sensor.
- Alcohol sensors like the MQ3 use a metal oxide semiconductor to detect alcohol concentrations between 25-500 ppm based on changes in resistance
ROBOTICS – SENSORS AND MACHINE VISION
Requirements of a sensor, Principles and Applications of the following types of sensors- Position sensors - Piezo Electric Sensor, LVDT, Resolvers, Optical Encoders, pneumatic Position Sensors, Range Sensors Triangulations Principles, Structured, Lighting Approach, Time of Flight, Range Finders, Laser Range Meters, Touch Sensors ,binary Sensors., Analog Sensors, Wrist Sensors, Compliance Sensors, Slip Sensors, Camera, Frame Grabber, Sensing and Digitizing Image Data- Signal Conversion, Image Storage, Lighting Techniques, Image Processing and Analysis-Data Reduction, Segmentation, Feature Extraction, Object Recognition, Other Algorithms, Applications- Inspection, Identification, Visual Serving and Navigation.
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Study on impedance variable type semiconductor gas sensor
- 1. Study on Impedance Variable Type Semiconductor Gas Sensor| ISweek - Industry sourcing Metal-oxide semiconductor gas sensors are effective to air environment monitoring and indoor gas leakage detection, etc., because of the high sensitivity property. The principle of the sensor operation is the oxidation or the reductive reaction caused by gas molecules with the film surface heated to a high temperature. The electrical resistance of the sensor changes by this reaction. It is possible to operate as a sensor of the impedance change type by adopting Interdigital Electrodes (IDEs) for the electrode that measures the electric characteristics of the Metal-oxide semiconductor film. The equivalent circuit of the sensor with IDEs depend on the heater voltage. When the general heater voltage is given (Drive at a high temperature), the sensor almost becomes pure resistance. On the other hand, it operates as a parallel equivalent circuit of R-C when the voltage is set low (Drive at the vicinity of room temperature). In the case of high temperature driving mode, the sensor functions as a sensor of the change in resistance type by the oxidation and the reductive reaction of the old model. In the case of low temperature driving mode, the sensor functions as impedance changeable sensor by a conductivity change and a permittivity change of the film. Those changes are caused by the physical adsorption of gas molecules. In this report, the principle of impedance changeable semiconductor gas sensor and the response characteristic of the sensor are described. ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products