Sensors & Transducers: Smart Sensors Unit 4 Part 5

Que5.1. Explain smart detectors. 


1. A smart detector is simply expanded as “ seeing, Monitoring and Remote  Transmission ” detector. 

2. It can be of either analog type or digital type which can be combined with  a processing unit and a communication interface. These detectors can   give an electrical affair. 

3. When they combined with suitable interfacing  bias, these detectors  are also called intelligent detectors. 

4. It can be defined as a microprocessor- grounded detector which can perform  one or  further number of the functions like logical functions, decision  making, two- way communication, etc. It can be simply expressed as,  Detectors Suitable interfacing circuits =  Smart detectors 

5. Smart detectors are different from conventional type detectors due to their  special functions  similar as ranging, estimation, communication with other   bias,etc. 

Que5.2. Give the features of smart detectors. 


1. Automatic ranging. 

2. bus estimation of data through an in-  erected system. 

3. Automatic data accession system and  storehouse of data in original memory  of the field device. 

4. bus linearization ofnon-linear functions. 

5. bus correction of  equipoises, time and temperature drifts. 

6. tone tuning control algorithms. 

7. Easy communication through  periodical  machine. 

Que5.3. What are the advantages of smart detectors? 

Answer  1. No need of bulk  lines and connectors Since smart detectors are of  electronic circuits, there’s no need to use any bulk cabling and connectors,  and hence overall cost of the system gets reduced. 

2. Digital communication Due to the integrated manner, the smart  detectors can  give digital communication. They also have an in-  erected   tone test or  individual  installation. 

3. Enhanced features Smart detectors are having enhanced features  like  tone-  calculation, fault diagnostics, duplex communication, multi   seeing, etc. Hence, they will be preferred in all kinds of control system. 

4. trustability Reduced wiring and capability to  give  tone- test and  diagnostics make the detectors more  dependable to use. 

5. Advanced SNR The electrical characteristic problems with the conventional  detectors are overcome by the use of smart detectors. There’s no noise   hindrance in smart detectors due to no  operation of long transmission   lines. 

6. Advanced characteristics bettered linearity when compared with  conventionalnon-linear characteristics, reducedcross-sensitivity,  reduced  neutralize and automatic are some of the important characteristics  of a smart detector. 

Que5.4. bandy the armature of smart detectors. 

Answer  1. The simple structure of any smart detector is shown inFig.5.4.1. The   seeing element and signal  exertion are combined to develop a  transduction element. 

2. The detailed armature of a smart detector is shown inFig.5.4.2. 

3. The  factors present in the armature of a smart detector are given  as follows  Transduction  rudiments( transducers) 

ii. Interfacing  tackle( data accession system) 

iii. Memory  tackle  iv. Programming  bias  Communication  installations  

vi. Compensation  installations. 

4. From the armature, there are several amplifiers( A1, A2, A3 and A4)  and sample and hold circuits( S/ H1, S/ H2, S/ H3 and S/ H4) corresponding  to different transducers( Transducer 1, Transducer 2, Transducer 3 and  Transducer 4) independently. 

5. To  gain the digital signal, the analog signals are  transferred to ADC via  analog MUX. Any type of ADC like flash type,  consecutive approximation  type or binary  pitch type ADC can be preferred grounded on  needed conversion  time constraint. 

6. neutralize compensation and correction circuits are also  handed along  with the processor. 

7. These circuits are useful for the  neutralize correction and zero compensation  purpose against temperature drift. For the data  storehouse and  reclamation,  memory is also available in the smart detector. 

Que5.5. Explain the  factors of smart detectors. 

Answer  seeing  rudiments  1. Detectors along with the signal  exertion circuits or simply transducers  are used as  seeing purpose. 

2. They’re in contact with the real world signals or measuring systems.  Any variables  similar as temperature, pressure, inflow,  position,etc., can be  measured with them. 

3. They’re also called a primary  seeing part of any  dimension system.  Data accession system( DAS) 

1. It can be used for the  dimension and processing of any real world  signal, or the variable which is to be measured, before being covered,  displayed or recorded. 

2. It consists of transducers, amplifiers, sample and hold  bias, multiplexer  and analog to digital conversion circuits. 

1. still, it’s necessary to use  If detectors are available for transductionpurpose.signal processing units to reuse the affair signals. 

2. They will do the process of modifying or manipulating the input signal in  such a way that they should meet the conditions for  farther  processing.  3. The process of signal  exertion is carried out by the following  way  Excitation 

a. For  unresistant transducers, it’s essential to supply the power.  Signal conditioning circuit itself generates excitation or power  force  to the  unresistant transducers  similar as strain hand, RTD, andetc. , current  If RTD is used as detector for temperaturemeasurement.excitation source can be used to convert change in resistance grounded  on temperature variation into measurable voltage. 

ii. Modification For the purpose of  adding  the resolution and  reducing the noise, amplifiers are used which will do boosting of input  signals. 

iii. Filtering To remove the unwanted noise  factors present in the  input signals, pollutants are  needed. Depending on the input signal, LPF or  HPF can be preferred. 

iv. Linearization For better response,non-linear response can be  converted into direct response by means of linearizing circuits.  Testing The process of conversion of  nonstop signal into  separate  signal is called  slice. 

vi. ADC/ DAC An analog to digital motor( ADC) can be used to convert  physical  volume(  nonstop nature) into digital  volume, whereas the  digital  volume can be converted into  nonstop analog  volume by  means of a digital to analog motor( DAC). 

vii. Sample and Hold( S/ H) circuit 

1. Sample and hold circuit is a device which samples the voltage of  continuously varying analog nature. 

2. Further the value can be hold at a constant  position for a specified period of  time. 

3. In any ADC circuit, sample and hold circuit can be used to  exclude the  variation in the input signal which corrupts the conversion process. 


1. It’s selection device which selects one of the several analog or digital  input signals and the  named signal will  also be  encouraged to a single  line. 

2. still, a multiplexer is used to  elect  If there are 2n inputs has n chooserlines.a particular input signal to be  transferred to a single line.  Programming  bias After the process of data accession process,  the reused affair signal is fed to the programming device  similar as  microprocessor unit for the purpose of programming.  Memory For the purpose of  storehouse and  reclamation of programmed  data, memory unit can be used. 

Que5.6. What are the  operations of smart detectors? 

Answer  1. Smart accelerometers for the  dimension of acceleration. 

2. Smart  optic detectors for object discovery. 

3. Smart IR sensor array for the identification of presence of products. 

4. Smart detector for  disfigurement or fractures covering in structures or  architectures. 

5. Smart detectors to  descry the minerals present in geological areas.  6. Food processing and preservation. 

7. natural hazard discovery. 

8. Health monitoring and medical diagnostics.

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