Resistance Temperature Detector (RTD) or Resistance Thermometers

Resistance Temperature Detector (RTD) It is a device which senses the resistance change on account of temperature change. This property is used for measurement of temperature. Resistance Temperature Detector (RTD) is also called as a resistance thermometer. It uses the change in electrical resistance to measure the temperature. Construction of RTD RTD elements consist of […]

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Thermistors Characteristics | Advantages & Applications

Fig. NTC Thermistors (source: ussensor.com)   Thermistors These are the thermally sensitive resistors. The resistance of a thermistor varies as a function of temperature. The thermistor is also called thermal resistors. It is a resistive temperature transducer. Thermistors are composed of semiconductor materials.  It is composed of a sintered mixture of metallic oxides such as Mn, […]

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Linear Variable Differential Transformer (LVDT) | Advantages & Applications

Fig: LVDT cross-section (source: te.com )   Linear Variable Differential Transformer (LVDT) is an inductive transducer that we discussed in the previous article. It is basically used to translate linear motion into electrical signals. LVDT Construction LVDT consists of one primary winding and two secondary windings. All these windings are wound on a cylindrical former. […]

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Potentiometer transducer | Advantages & Applications

Fig. Resistive Potentiometers (POT) (source: instructables.com) Potentiometer  A potentiometer consists of a resistive element having a sliding contact. This sliding contact is known as a wiper. A potentiometer is also called as POT because it is used in voltage division. It is a resistive and passive transducer.   Depending upon the motion of wiper, potentiometer are […]

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Strain Gauge Working Principle & Applications

Fig. Strain Gauges (source: omega.com)   Strain gauge A strain gauge is an electrical transducer which is used for measuring mechanical surface strain. Basic Principle of Strain Gauge When stress is applied to the metal conductor, its resistance changes owing to change in length and cross-sectional area of the conductor. The resistance of the conductor under […]

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Thermocouple Working | Advantages & Applications

Fig. Thermocouple (source: sterlingsensors.co.uk)   What is a Thermocouple? A thermocouple consists of a pair of dissimilar wires joined at one end. It is an active transducer. On the other hand, RTD and thermistors are passive transducers. Thermocouple work on the principle of Seebeck effect. According to Seebeck effect, if two dissimilar metals are joined together […]

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Piezoelectric Transducer | Advantages & Applications

Piezoelectric Transducer A piezoelectric transducer is one that can generate a voltage proportional to the stress applied to it. These transducers work according to the piezoelectric effect. When a mechanical force or pressure is applied across the piezoelectric crystal, an electric potential appears across the surfaces of crystal. This generation of electric potential is due […]

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Hall Effect Transducers | Advantages & Applications

Hall Effect Transducers Hall Effect Transducers are the transducers which work on the principle of hall effect. According to hall effect, if a conducting material strip carries current in the presence of a transverse magnetic field; an EMF is produced between two edges of the conductor in a direction perpendicular to both the magnetic field […]

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Hay’s bridge for Measurement of Inductance

In the previous article, we have learned about Maxwell bridge. It is a modification of Maxwell’s bridge. The circuit diagram for Hay’s Bridge is shown below. It uses a resistance in series with a standard capacitor. L1=unknown resistance having a resistance R1 R2, R3, R4=known non-inductive resistance C4=standard capacitor At balance, e1e4 = e2e3 Separating real […]

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