Resolvers Working Principle & Applications
Resolver source: designworldonline.com Resolver is a synchro whose rotor is mechanically driven to translate rotor angle into electrical information corresponding to the sine and cosine of rotor angle. It can interchange rectangular and polar coordinates. It is also called a sine-cosine generator and synchro-resolver. It is an analog device. A…
Rotary Variable Differential Transformer (RVDT) Working Principle & Applications
Figure. RVDT In previous article, we have learned about Linear variable differential transformer (LVDT). Rotary Variable Differential Transformer (RVDT) is a variation of LVDT and used to sense angular displacement. It is a passive transducer. In short, RVDT provides a variable alternating current (AC) output voltage that is linearly proportional to…
Linear Variable Differential Transformer (LVDT) Working Principle & Applications
Fig: LVDT cross-section (source: te.com ) Linear Variable Differential Transformer (LVDT) is an inductive transducer that we discussed in 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…
Hall Effect Transducers Working Transducers & Applications
Hall Effect Transducers are the transducers which works 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 conductor in a direction perpendicular to both the magnetic…
Piezoelectric Transducer Working Principle & Applications
Piezoelectric Transducer Piezoelectric transducer are one that can generate a voltage proportional to the stress applied upon it. These transducers work according to piezoelectric effect. When a mechanical force or pressure is applied across piezoelectric crystal, an electric potential appears across the surfaces of crystal. This generation of electric potential…
Inductive Transducers Working Principle & Applications
Fig. Inductive Transducers (source: eddylab.com) Inductive Transducers In Inductive transducers, the basic principle is that self-inductance of a single coil or the mutual inductance between two coils is changed by a quantity to be measured i.e. measurand. Usually, the measurand could be a rotary or linear displacement, force, pressure, torque,…
Capacitive Transducers Working Principle & Applications
Fig. Capacitive transducers (source: directindustry.com) Capacitive Transducers The capacitive transducer is the capacitor with variable capacitance. The capacitive transducer consists of two parallel metal plates that are separated by the dielectric material such as air. We are familiar with the equation of capacitor which is given as In a normal…
Thermocouple Working Principle & Applications
Fig. Thermouple (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…
Strain Gauge Working Principle & Applications
Fig. Strain Gauges (source: omega.com) Strain gauge Strain gauge is an electrical transducer which is used for measuring mechanical surface strain. Basic Principle of Strain Gauge When stress is applied on the metal conductor, its resistance changes owing to change in length and cross-sectional area of the conductor. The resistance of…
Thermistors Characteristics & 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. Thermistor are also called as thermal resistors. It is a resistive temperature transducer. Thermistors are composed of semiconductor materials. It is composed of sintered mixture of metallic oxides…