Hall transducers

These levels are for fully disassentbled equipment in free air, as measured by a calibrated Hall transducer. 

Norton, H. N., Handbook of Transducers for Electronic Measuring Systems, Prentice-Hall, Englewood Cliffs, NJ (1969). 

Other types of transducers used in process measurements include mechanical drivers such as gear trains and electrical drivers such as a differential transformer or a Hall effect (semiconductor-based) sensor. 

The operation of proximity sensors can be based on a wide range of principles, including capacitance, induction, Hall and magnetic effects variable reluctance, linear variable differential transformer (LVDT), variable resistor mechanical and electromechanical limit switches optical, photoelectric, or fiber-optic sensors laser-based distance, dimension, or thickness sensors air gap sensors ultrasonic and displacement transducers. Their detection ranges vary from micrometers to meters, and their applications include the measurement of position, displacement, proximity, or operational limits in controlling moving components of valves and dampers. Either linear or angular position can be measured ... 

One of the most popular and relatively inexpensive measurements is the power consumption of the main mixer motor. It is measured by a watt transducer or a power cell utilizing Hall effect (a measurable trans-versive voltage between the two radial sides of a current conductor in a magnetic field, an effect discovered by E.H. Hall in 1879). 

Active sensors require an external power supply for operation. This is the 5 or 12 V system of the ECU. The main technologies are the complementary metal-oxide semiconductor Hall-effect transducers (CMOS-Hall) or AMR (anisotropic magnetoresistive effect) plus silicon amplification [3],... 

Figure 6.30 also shows that a Hall effect transducer and a voltage isolation amplifier are used in the system, which provides independent measurement of the pulsed current and voltage drop between the two rams, respectively. The RMS values of the electrical variables are important for the correct evaluation of the Joule heat distribution, which is demonstrated by the comprehensive analysis of the system behavior from the electromagnetic perspective. With these instantaneous measurement results, the corresponding average values of various parameters can be calculated as [42] ... 

When a biologically active material interacts with an analyte, a physicochemical change takes place that is converted into an electrical output signal using a suitable transducer. Based on various types of transducers, biosensors may be classified into optical, calorimetric, piezoelectric and electrochemical biosensors. Cooper and Hall have reported the electrochemical response of a GOD loaded PANI film [84]. Mu and co-workers have studied the bioelectrochemical response of the PANI-uricase electrode [162]. 

In the case of actively controlled structural dynamics, sensors may measure a variety of signals, such as accelerations (accelerometers), displacements (Hall sensors, capacitive sensors, laser interferometers, etc.), forces (force transducers), or - typically for adaptronic structures - strain or strain velocities (strain gauges, piezoelectric sensors, etc.). Most of these cases can be represented by the following sensor equation ... 

Because of these complicating effects it can be advantageous to determine 544 and 566 froni experiments in simple shear. Lewis, Richardson and Ward [13] have used a Hall effect transducer to measure this type of deformation and obtain shear compliances that agree with those measured in torsion. 

Several transducers produce output voltages related to concentration or to a physical quantity of interest. For example, ion-selective electrodes produce voltage outputs related to pH or the concentration of an ion in solution. Thermocouples produce voltage outputs related to temperature. Similarly, Hall effect transducers produce output voltages proportional to magnetic field strength. Operational amplifier circuits, particularly those based on the voltage follower (see Section 3B-2), are used extensively for such measurements. 

Pressure-sensing elements (a) flat diaphragm (b) corrugated diaphragm (c) capsule (d) bellows (e) straight tube (f) Cshaped Bourdon tube (g) twisted Bourdon tube (h) helical Bourdon tube (i) spiral Bourdon tube. (From Norton, H.N., Handbook of Transducers, Englewood Cliffe, NI Prentice-Hall, 1989, 294-330. Reprinted with permission.) Previously published in Chau, K.H.L., Pressure and sound measurement, in The Measurement, Instrumentation, and Sensors Handbook, Webster, I.G., Ed., CRC Press, Boca Raton, FL, 1999, p. 26-3.)... 

Electrical tachometer Hall effect sensor Capacitive transducer... 

The sample s equilibrium dimensions were measured by means of a stereo microscope as a function of temperature in a bath of de-ionized water, while the length-time behaviour of hydrogel samples submitted to free swelling experiments was detected by means of a Hall effect isotonic transducer connected to a computer acquisition data... 

Patranabis, D., 2003. Sensors and Transducers, second ed. Prentice-Hall, New Delhi. 

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