Barium titanate They are sensitive to stray magnetic fields, therefore, magnetic shielding is necessary. As the core moves in one direction away from the NULL position, voltage in one secondary increases while in the other secondary decreases i.e. c) Both S1 & S2 are true b) Digital plethysmography The LVDT (see Figure 15.3.2) is a position-to-electrical sensor whose output is proportional to the position of a movable magnetic core.The core moves linearly inside a transformer consisting of a center primary coil and two outer secondary coils wound on a cylindrical form. The output of the LVDT is AC signal, therefore, a demodulator network must be used if a DC output is required. Fiber optic sensor can be used to sense _________, a) Displacement Let us assume that the secondary voltage of the RVDT transformer is Es21 and Es22, respectively. Typically, a sinusoidal 3-Vac RMS voltage between 2.5 and 10 kHz excites the primary winding. d) Both S1 & S2 are false, 27. c) Dialysate flow in artificial kidney The LVDT has high sensitivity. Advantages of LVDT. 4. b. 1. S2: Transducer is also called as sensor. Most commonly used indicator electrode is, a) Calomel electrode 37. Principle of Operation and Working. Measurement and Instrumentation Objective Questions. An inverse transducer is a device which converts, a) An electrical quantity into a non electrical quantity Under normal condition of RVDT, the flux linkage of both the secondary winding are same due to their symmetrical placing w.r.t. It posses high sensitivity, typically about 40 V/mm. If you continue to use this site we will assume that you are happy with it. Pick the correct statement regarding functions of a transducer, S1: Sense the magnitude, change in & / or frequency of same measurand b) Parabolic path The most widely used variable-inductance displacement transducer in Industry is a Linear Variable Differential Transformer (LVDT). It gives higher output for small change in magnetic core position. b) Strain gauge or capacitive transducer d) Permanence, a) Magneto-strict ion c) Resistive transducer Whereas, the sensitivity of the RVDT is in the range of 2 to 3mv per volt per degree of rotation. High Output and High Sensitivity: The LVDT gives high output and many times there is no need for amplification. High Output: The LVDT gives reasonably high output and hence requires less amplification. Which of the following can be measured with the help of piezo electric crystal? An LVDT, or Linear Variable Differential Transformer, is an inductive device containing primary and secondary coaxial wound coils, and a ferromagnetic core. b) Dynamic d) Pulse transducer. Handle all equipments with care. d) Self generating transducer, 32. As the core moves closer to either of the secondary coils, the induced voltage in that coil increases, and the induced … 2. b) Power A movable soft iron core is placed inside the former. a) LDR Time Response of Second Order Systems – IV. 27. A Linear Variable Differential Transformer (LVDT) is a displacement transducer, used to measure displacement, based on the effect of the mutual inductances. The primary winding is connected to an AC voltage source. Self generating type transducers are _____ transducers. 24. Photo conductive cell consists of a thin film of, a) Quartz b) Finger movement Required fields are marked *. c) Electrical energy into thermal energy ________ fiber is used in interferometric instruments. 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