ekt314/4 electronic instrumentation

EKT314/4Electronic

InstrumentationWeek 2

Chapter 2: Transducer

EKT314/4 - Electronic Instrumentation 2

Review Last LectureIntroduction to Electronics

Instrumentation


Transducer

Signal Conditione

rFilter

Excitation Power Supply

Controller Interface

Micro-processor

D2A Converter

Signal Digital Display

A2D Converter

Analog Subsystem

Analog Display

Digital Printer

Digital Storage

Tape Recorder

Oscilloscope

Oscillograph

XY PlotterTo ProcessControl System

To digital controller /Computer interface

Complete Block Diagram


Block Diagram - Review

Simplified Block Diagram


Intro to EI

Overview

Process Control

Engineering Analysis

Block Diagram

Application

Terminology

Application Area: Engineering Analysis

Engineering Analysis› To validate new design of structure,

component or system by theoritical and experimental approach


Intro to EI

Overview

Process Control

Engineering Analysis

Block Diagram

Application

Terminology

Application Area: Process Control

Process Control› Monitoring process: provide real-time data that

allow operator to respond.› Automatic process: provide real-time feedback

data to the control system.


Motivation & DefinitionThe word 'sensor' is derived from entire

meaning 'to perceive' and 'transducer' is derived from transducer meaning 'to lead across'.device that detects a change in a physical stimulus and turns it into a signal which can be measured or recorded;


Motivation & Definition definition of 'transducer' is 'a device that transfers power from one system to another in the same or in the different form'.A sensible distinction is to use 'sensor' for the sensing element itself and 'transducer' for the sensing element plus any associated circuitry. All transducers would thus contain a sensor and most (though not all) sensors would also be transducers.[1]

[1]http://www.mfg.mtu.edu/cyberman/machtool/machtool/sensors/intro.html


Transducer


Transducer

ComputerScience


Transducer

Physics ComputerScience


Transducer



Transducer


FiniteState


Transducer


FiniteState

Definition


Transducer


FiniteState

Definition

Classification


Transducer


FiniteState

Definition

Classification

Applications


Definition Transducer is a device that converts one type

of energy to another. Energy types include (but are not limited

to) electrical, mechanical, electromagnetic (including light), chemical, acoustic or thermal energy.

The term transducer commonly implies the use of a sensor/detector, any device which converts energy can be considered a transducer.

Transducers are widely used in measuring instruments.


Definition – Block Diagram

Source - http://www.instrumentationtoday.com/2011/07/




Sensing ElementThe physical quantity or its rate of change is sensed and responded to by this part of the transistor.


Transduction ElementThe output of the sensing element is passed on to the transduction element. This element is responsible for converting the non-electrical signal into its proportional electrical signal.



Sensing ElementThe physical quantity or its rate of change is sensed and responded to by this part of the transistor.


Definition – Selection Selection depends on the physical

quantity to be measured. Depends on the best transducer

principle for the given physical input. Depends on the order of accuracy to be

obtained.


Transducer

Physics

Definition

Classification

Applications


Transducer

Physics

Definition

Classification

Applications

Physical


Transducer

Physics

Definition

Classification

Applications

Physical

Behavior


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

Active-Passive


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

MechanicalActive-Passive


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

Mechanical

Electrical

Active-Passive


Mechanical Transducer Mechanical elements that are used for

converting one form of energy into other form.


Transducer

Classification

Physical

Mechanical

ElectricalBellowsBourdon TubeSpringProving RingsDiaphragmManometerThermocoupleBimetalsHydro-pneumatic

Source - http://www.brighthub.com/engineering/mechanical/articles/41946.aspx


Physical

Mechanical



Elastic elements that convert the air pressure into displacement, and it is commonly used for the measurement of pressure.

Transducer

Classification


Mechanical



This elastic tube converts air pressure to the rotary motion of the pointer used to indicate the pressure.

Physical

Transducer

Classification


Mechanical



The spring tend to expand when force is applied to them, thus they are used for the measurement of force.

Physical

Transducer

Classification

Spring Limit Sensor


Mechanical



Like the springs the proving rings also convert applied force to the displacement.

Physical

Transducer

Classification

Used for compression and Tension Measurements


Mechanical



It converts applied pressure to the displacement.

Physical

Transducer

Classification

YOKOGAWA EJX438A Diaphragm Sealed Gauge Pressure Transmitter


Mechanical



Converts the applied pressure into variable displacement of the liquid within it enabling to measure the pressure.

Physical

Transducer

Classification


Mechanical



Produces electric current when one of its end is heated enabling us to measure the temperature.

Physical

Transducer

Classification


Mechanical



Bimetallic strips comprising of two different metals having different coefficient of thermal expansion, joint together to indicates the temperature.

Physical

Transducer

Classification


Mechanical



These include devices like orifice, venturi, pitot tube, vanes and turbines that are used for measurement of pressure, velocity, flow rate and force of water.

Physical

Transducer

Classification


Mechanical



Apart from the mechanical transducers mentioned above there are many others like seismic mass, pendulum scale, float etc.

Physical

Transducer

Classification


Mechanical Transducer Most of the mechanical transducers are

used as the primary transducers, meaning the initial input is applied to them, while the output obtained from them can be used directly to measure the quantity or it can be given as input to the secondary transducer, which are

mostly of electrical type.


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

Mechanical

Electrical

Active-Passive


Electrical Transducer The transducers that convert the mechanical

input signals of the physical quantity into electrical output signals.

The input given can be in the form of the displacement, strain, velocity, temperature, flow etc and the output obtained from them can be in the form of current, voltage and change in resistance, inductance and capacitance.

The output can be measured easily and it is calibrated against the input, thus enabling the measurement of the value of the input.


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

Active-Passive


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

Sensor

Active-Passive


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

Actuator

Sensor

Active-Passive


Sensor A sensor (also called detector) is a device that

measures a physical quantity and converts it into a signal which can be read by an observer or by an instrument.

Ex: a mercury-in-glass thermometer converts the measured temperature into expansion and contraction of a liquid which can be read on a calibrated glass tube.

Ex: A thermocouple converts temperature to an output voltage which can be read by a voltmeter.

For accuracy, most sensors are calibrated against known standards.


Transducer

Physics

Definition

Classification

Applications

Physical

BehaviorConversion

Application

Actuator

Sensor

Active-Passive


Actuator An actuator is a type of motor for moving or

controlling a mechanism or system operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or pneumatic pressure, and converts that energy into some kind of motion.

An actuator is the mechanism by which an agent acts upon an environment. The agent can be either an artificial intelligent agent or any other autonomous being (human, other animal, etc).


Transducer

Physics

Classification

BehaviorConversion

Application

Physical

Source – http://en.wikipedia.org/wiki/Transducer

Active-Passive

DefinitionApplication

s


Transducer

Physics

Classification

BehaviorConversion

Application

ElectromagneticElectrochemicalElectromechanicalElectroacousticPhotoelectricElectrostaticThermoelectricRadioacoustic

Physical


Active-Passive


Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

AntennaCathode ray tube (CRT)Fluorescent lamplight bulbMagnetic cartridgePhotodetectorPhotoresistorLight dependent resistor (LDR)Tape headHall effect sensor



Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

pH probesElectro-galvanic fuel cellHydrogen sensor



Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

Electroactive polymersGalvanometerRotary motor, linear motorVibration powered generatorPotentiometerLoad cellAccelerometerStrain gaugeString potentiometerAir flow sensorTactile sensor



Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

Loudspeaker, earphoneMicrophonePickup (music technology)Tactile transducerPiezoelectric crystalGeophoneGramophone pickupHydrophoneSonar transponder



Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

Laser diodeLight-emitting diodePhotodiodePhotoresistorPhototransistorPhotomultiplier tube



Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

Electrometer



Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

Resistance temperature detector (RTD)ThermocouplePeltier coolerThermistor



Transducer

Physics

Classification

BehaviorConversion

Application


PhysicalExamples:

Geiger–Müller tubeReceiver (radio)




s

Transducer

Physics

Classification

BehaviorConversion

Application

PhysicalActive-Passive



s

Transducer

Physics

Classification

BehaviorConversion

Application


Pressure Displacement ForceTorqueTemperature Sound Power Current Magnetic Flux Vibration Velocity Light Position Humidity etc.



s

Transducer

Physics

Classification

BehaviorConversion

Application



Definition

Transducer

Physics

Classification

BehaviorConversion

Application


Passive


Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive


Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive

Resistance Variation TypeCapacitance Variation TypeInductance Variation TypeVoltage and Current Type


Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive


Examples:Resistance Strain GaugeResistance ThermometerResistance HygrometerHot Wire MeterPhotoconductive CellThermistor Potentiometer Type

Source – http://www.instrumentationtoday.com/2011/07/


Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive


Examples:Variable Capacitance Pressure GaugeDielectric GaugeCapacitor Microphone



Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive


Examples:Eddy Current TransducerVariable Reluctance TypeProximity Inductance TypeDifferential TransformerMagnetostrictive Transducer



Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive


Examples:Photo-emissive CellHall EffectIonisation Chamber



Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive

Examples:Photo-voltaic CellThermopilePiezoelectric TypeMoving Coil Type



Definition Active

Transducer

Physics

Classification

BehaviorConversion

Application


Passive



EKT314/4Electronic

Instrumentation

Week 2End

ekt314/4 electronic instrumentation

Documents

transducer review

automatic process

finite state automaton

realtime data

finite number of states

relational composition

sensing element

different states