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Hydro Electric Power-PlantInstrumentation
1
Dr. R. P. Maheshwari
Professor Department of Electrical Engineering
Indian Institute of Technology Roorkee
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Topics covered in this module
Measurement techniques of level, flow, pressure andtemperature
Hydraulic heads and mechanical vibrations
Temperature scanners
Alarm annunciations
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References
1. Industrial Instrumentation and Control by: S. K. Singh(Tata McGraw Hill Publication, 3rd edition)
2. Power Plant Engineering by: B. L. Singhal (Tech-MaxPublications, 2010 edition)
3. Modern power Station Practice, Volume F: Controland Instrumentation, British Electricity international(Pergamon Press, 1990 / 2003 edition)
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Units of Measure
System Length Force Mass Time Pressure
MKS Meter Newton Kg Sec N/M 2 =
PascalCGS CM Dyne Gram Sec D/CM 2
English Inch Pound Slug Sec PSI
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Level Measurement
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Level MeasurementGenerally, there are two methods used in industries for measuringliquid level.
(1) Direct methods
(2) Indirect methods
(i) Hook up type level indicator(ii) Sight Glass(iii) Float-type
(i) Hydrostatic pressure type(ii) Electrical methods
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Measurement Measurement is the process of assigning numbers to quantities.
The process is so familiar that perhaps we often overlook itsfundamental characteristics.
Properties of Quantities Quantities that we can measure have a number of properties.
For example, a quantity can be discrete or continuous .
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Level Measurement with radar and Ultrasonic
Through Air Radar
Guided WaveRadar
Ultrasonic
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Level Measurement
How it works
The time it takes for the instruments signal toleave the antenna, travel to the product, andreturn to the antenna is calculated intodistance.
The instrument is spanned according to thedistance the 100% and 0% points within thevessel are from its reference point .
The measured distance can then be convertedinto the end users desired engineering unit
and viewed on the head of the instrument or remote display.
100%
0%
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Level Measurement
How do process conditions affect thereliability and accuracy of process leveltransmitters ?
density (specific gravity)?dielectric constant?
conductivity?temperature?pressure?vacuum?agitation?
vapors and condensation?dust and build up?internal structures?
Process conditions that affect specification of transmitters
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Level MeasurementRadar Technology How it works
Radar is a time of flight measurement.
Microwave energy is transmitted by theradar.
The microwave energy is reflected off the
product surface
The radar sensor receives the microwaveenergy.
The time from transmitting to receiving themicrowave energy is measured.
The time is converted to a distancemeasurement and then eventually a level.
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Level MeasurementFunction of an antenna
Signal focusing reduction of the antenna ringing optimization of the beam
Signal amplification focusing of the emitted signal
amplification of the receipt signal
Signal orientation point at the product surface
minimization of false echo reflections
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Level Measurement
Radar level measurement
Top mountedSolids and liquids applicationsNon-contact
RADAR is virtually unaffected by the followingprocess conditions:
TemperaturePressure and VacuumConductivityDielectric Constant (dK)Specific Gravity
Vapor, Steam, Dust or Air MovementBuild up (depends on radar design)
Radar Technology Why use it?
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Level MeasurementRadar Technology - Choice of frequency
Radar wavelength = Speed of light / frequencyl = c / f
Frequency 6.3 GHz
wavelength l = 47.5 mm
Frequency 26 GHzwavelength l = 11.5 mm
High frequency:
shorter wavelength
narrower beam angle
more focused signal
ability to measure smaller vesselswith more flexible mounting
47.5mm
Low frequency:
longer wavelength
wider beam angle
less focused signal
ability to measure in vessels withdifficult application variables
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Level Measurement
Frequency
Choosing a frequency depends on:
Mounting optionsCustomers 100% point
Vessel dimensions proximity of connection to sidewallThe presence of foamAgitated product surfacesVapor compositionVessel internal structuresDielectric constant (dK)
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Level Measurement
Guided Wave
Radar (TDR)
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Level Measurement
Guided Wave Radar level measurement
Time of Flight Top mounted Solids and liquids applications Contact Measurement
GUIDED WAVE RADAR is virtually unaffected bythe following process conditions:
TemperaturePressure and VacuumConductivityDielectric Constant (dK)Specific GravityVapor, Steam, or Dust Air MovementBuild up (depends on type of build up)Foam
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Level Measurement
Ultrasonic
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Level Measurement
Ultrasonic level measurement
Time of FlightTop mountedSolids and liquids applications
Non-contact
ULTRASONIC is virtually unaffected by thefollowing process conditions:
Change is product density (spg)Change in dielectric constant (dk)
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Level MeasurementUltrasonic Level Measurement How it works
Time of Flight Technology
Short ultrasonic impulses emitted fromtransducer
Bursts are created from electrical energy
applied to piezeo electric crystal inside thetransducer
The transducer creates sound waves(mechanical energy)
With longer measuring ranges a lower frequency and higher amplitude are neededto produce sound waves that can travelfarther
The longer the measuring range thelarger the transducer must be
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Level MeasurementUltrasonic Level Technology Advantages
Can be mounted in plastic stilling wells
Narrow beam angles minimize effect of obstructions
Swivel flange available for applications with
angles of repose
Familiar technology throughout the industry,therefore, often a trusted technology throughoutthe industry
Cost-effective
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Flow Measurement
Flow rate may vary from few drops per hour to thousands of gallonsper minute. Range abilities may vary from essentially 1:1 to 100:1 orgreater.
(i) Inferential type flow meters(ii) Quantity flow meters(iii) Mass flow meters
(i) Variable head or differential meters(ii) Variable area meters
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Flow Measurement
Typical types in industries
(i) Orifice Plates(ii) Venturi Tubes(iii) Flow Nozzles(iv) Pitot Tubes
(v) Rotameters(vi) Magnetic flow meters(vii) Thermal flow meters(viii) Vortex flow meters
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Flow MeasurementPrinciples of Flow
Q = Pressure/Resistance
Laminar
Turbulent
l
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Flow MeasurementFluid flow steam line
Occurs at low velocities All parts flowing in one direction parallel to walls Change in cross section means change in direction of flow Pressure drop flow velocity
Fl M
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Flow MeasurementFluid flow - turbulent
Liquid behaves as independent entities
Pressure varies with Kinetic energy
Proportional To square of turbulent flow velocity
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Flow Measurement Principle
P1
P2Counterpressuresensor
flowin
flowout
l Electronic flow measurement principle- laminar flow restrictionscreate a pressure difference P 1 - flow is calculated from P 1
l Used with Oxygen, Side gas, Bypass, andAgent flows
Laminar flow restriction
P1Ambientpressure
P2
P1 = pressure difference
P2 = correction (off-set) to ambientpressure
Fl M
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Flow Measurement
Orifice meters
Fl M
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Flow Measurement
Pressure differences
Fl M t
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Flow Measurement
Diff. Pressure calculation
Fl M t
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Flow Measurement
Venturi meter
Fl M t
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Flow Measurement
Fl M t
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Flow Measurement
Flow nozzle
Flo Meas rement
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Flow Measurement
Pitot tube
Flow Measurement
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Flow Measurement
Flow Measurement
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Flow Measurement
Pressure Measurement
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Pressure Measurement
Pressure Sensors
In any given plant, the number of pressure gauges used is probably larger than all other instruments put together
Most liquid and all gaseous materials in the processindustries are contained within closed vessels. For the safetyof plant personnel and protection of the vessel, pressure inthe vessel is controlled. In addition, pressured is controlled
because it influences key process operations like vapor-liquidequilibrium, chemical reaction rate, and fluid flow.
Pressure Measurement
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Pressure Measurement
Pressure = Force / Area
Pressure can be used inferentially to measure other variables such asFlow and Level
Pressure plays a major role in determining the Boiling Point of Liquids
Fluids exerts pressure on the containing vessel equally and in alldirections
Pressure Measurement
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Pressure Measurement
How is pressure measured?
Absolute versus relative pressure
ManometryBourdon
AneroidStrain gauge
Pressure Measurement
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Pressure Measurement
Presiunereferinta
Pabs = 0
TR Pabs
Absolute Pressure
Pressure Measurement
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Pressure Measurement
hgP
AhgA0AP
hgabs
hgabs
P=0
Patm
h
h
A
Patm A
0
Well-type manometer
Barometer
Pressure Measurement
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Pressure Measurement
Pressure Measurement
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Pressure Measurement
12 PPP
P1P2
Differential Pressure
atm2 PPP
P2Patm
Pressure Measurement
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Pressure Measurement
Types of Pressure
Pressure Measurement
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Pressure Measurement
Static and Dynamic Pressure
Dynamic pressure = Stagnation pressure (A) - Static pressure (B)
Pressure Measurement
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Pressure Measurement
Types of Pressure Transducers
Liquid Column manometers Elastic tubes, diaphragms, membranes (equipped with
displacement or strain sensors)
Semiconductor elements (with implanted stress elements)
Piezoelectic elements (directly convert crystal lattice stress intovoltage)
Pressure Measurement
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Pressure Measurement
Differential Pressure
hgPP
AhgAPAP
12
12
P2
h h
A
P2 A
P1P1 A
U tube manometer
Pressure Measurement
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Pressure Measurement
hgPP
AhgAPAP
12
12
P2h h
A
P2 A
P1P1 A
Inclined Manometer
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r 12
r
r
12
12
h)sin(gPP
)sin(hh
hh
)sin(hgPP
AhgAPAP
P2h
h r
A P2 A
P1
P1 A
g
Pressure Measurement
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Pressure Measurement
Elastic elements
Changing pressurechange the shape of theelastic element
Shape changing is
detected by a resistive orposition transducer
Tip C Spirala Tubrasucit Elicoidal
TuburiBourdon
Capsula
Diafragme
P Absoluta
P Diferentiala
Plata
Ondulata
evacuat
Diferential sau absolut
Tub
Pressure Measurement
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Pressure Measurement
Elastic elements
Changing pressure change theshape of the elastic element
Shape changing is detected bya resistive or positiontransducer
Pressure Measurement
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Pressure MeasurementDial-type Manometer
Dial-type Manometer as a mini measurement system
Pressure Measurement
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Pressure Measurement
Diaphragm type manometers
To be able to detect pressure, we need to detect thediaphragm deflection
Pressure Measurement
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Bourdon
Pressure Measurement
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Aneroid
Pressure Measurement
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Strain gauges used with Diaphragm
Strain gage based pressure cell
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When a strain gage, is used tomeasure the deflection of an elasticdiaphragm or Bourdon tube itbecomes a component in pressuretransducer
Strain-gage transducers are used fornarrow-span pressure and fordifferential pressure measurements.
Essentially, the strain gage is used tomeasure the displacement of anelastic diaphragm due to adifference in pressure across thediaphragm
If the low pressure side is a sealed
vacuum reference, the transmitterwill act as an absolute pressuretransmitter.
Strain gage transducers are availablefor pressure ranges as low as 1300MPa
Capacitance based pressure cell
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Capacitance pressure transducerswere originally developed for use inlow vacuum research. Thiscapacitance change results from themovement of a diaphragm element
(The diaphragm is usually metal ormetal-coated quartz and is exposedto the process pressure on one sideand to the reference pressure onthe other. Depending on the type
Differential pressure transducers ina variety of ranges and outputs of pressure, the capacitive transducercan be either an absolute, gauge, or
differential pressure transducer. Capacitance pressure transducershave a wide range ability, from highvacuums in the micron range to 70MPa.
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Magnetic pressure transducers
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These included the use of inductance, reluctance, and eddy currents.Inductance is that property of an electric circuit that expresses the amount of electromotive force (emf) induced by a given rate of change of current flow inthe circuit.
Reluctance is resistance to magnetic flow, the opposition offered by magneticsubstance to magnetic flux.
In these sensors, a change in pressure produces a movement, which in turnchanges the inductance or reluctance of an electric circuit.
Optical pressure transducers
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Optical pressure transducers detectthe effects of minute motions due tochanges in process pressure and
generate a corresponding electronicoutput signal. A light emitting diode (LED) is used
as the light source, and a vaneblocks some of the light as it ismoved by the diaphragm. As theprocess pressure moves the vanebetween the source diode and themeasuring diode, the amount of infrared light received changes.
Optical pressure transducers do notrequire much maintenance.
They have excellent stability and aredesigned for long-durationmeasurements.
They are available with ranges from35 kPa to 413 MPa and with 0.1%full scale accuracy.
Temperature Measurement
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Types of temperature sensors
RTD (Resistance Temperature Detector)
Thermistor
Thermocouple
Temperature Measurement
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RTD, the basics
How it works: Utilizes the fact that
resistance of a metalchanges with temperature.
Make up: Traditionally made up of
platinum, nickel, iron orcopper wound around aninsulator.
Temperature range: From about -196 C to
482 C.
Thin Film RTD
Temperature Measurement
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RTD Advantages and Disadvantages
Advantages:
Stable
Very accurate
Change in resistance islinear
Disadvantages:
Expensive
Current sourcerequired
Small change inresistance
Self heating
Less rugged thanthermocouples.
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RTD
Resistivity of metals is a function of temperature. Platinum often used since it can be used for a wide temperature
range and has excellent stability. Nickel or nickel alloys are used aswell, but they arent as accurate.
In several common configurations, the platinum wire is exposeddirectly to air (called a bird-cage element), wound around a bobbin
and then sealed in molten glass, or threaded through a ceramiccylinder. Metal film RTDs are new. To make these, a platinum or metal-glass
slurry film is deposited onto a ceramic substrate. The substrate isthen etched with a laser. These RTDs are very small but arent asstable (and hence accurate).
RTDs are more accurate but also larger and more expensive thanthermocouples.
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RTD
From Nicholas & White, Traceable Temperatures.
Sheathing: stainless steel or iconel, glass, alumina, quartz
Metal sheath can cause contamination at high temperatures and arebest below 250C. At very high temperatures, quartz and high-purity alumina are best to
prevent contamination.
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RTD Resistance Measurement
Several different bridge circuits are used to determine theresistance. Bridge circuits help improve the accuracy of the measurements significantly. Bridge output voltage is afunction of the RTD resistance.
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RTD Resistance/Temperature Conversion
Published equations relating bridge voltage to temperature can beused.
For very accurate results, do your own calibration.
Several electronic calibrators are available. The most accurate calibration that you can do easily yourself is to
use a constant temperature bath and NIST-traceablethermometers. You then can make your own calibration curvecorrelating temperature and voltage.
Potential Problems
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RTD
RTDs are more fragile than thermocouples.
An external current must be supplied to the RTD. This current canheat the RTD, altering the results. For situations with high heattransfer coefficients, this error is small since the heat is dissipated toair. For small diameter thermocouples and still air this error is the
largest. Use the largest RTD possible and smallest external currentpossible to minimize this error.
Be careful about the way you set up your measurement device.Attaching it can change the voltage.
When the platinum is connected to copper connectors, a voltagedifference will occur (as in thermocouples). This voltage must besubtracted off.
Resistance/Temperature Conversion
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Standard thermistors curves are not provided as much aswith thermocouples or RTDs. You often need a curve for a
specific batch of thermistors.
No 4-wire bridge is required as with an RTD.
DAQ systems can handle the non-linear curve fit easily.
Thermistors do not do well at high temperatures andshow instability with time (but for the best ones, thisinstability is only a few millikelvin per year)
Temperature Measurement
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Thermistor, the basics of
How it works: Like the RTD a thermistor
uses the fact thatresistance of a metalchanges with temperature.
Make up: Generally made up of
semiconductor materials
Temperature Range: About -45 C - 150 C
Thermistor
Temperature Measurement
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Thermistor Advantages and Disadvantages
Advantages:
Very sensitive (has thelargest output change
from inputtemperature)
Quick response
More accurate than
RTD andThermocouples
Disadvantages:
Output is a non-linearfunction
Limited temperaturerange.
Require a currentsource
Self heating Fragile
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Thermistor
Thermistors also measure the change in resistance with temperature.
Thermistors are very sensitive (up to 100 times more than RTDs and1000 times more than thermocouples) and can detect very smallchanges in temperature. They are also very fast.
Due to their speed, they are used for precision temperature controland any time very small temperature differences must be detected.
They are made of ceramic semiconductor material (metal oxides).
The change in thermistor resistance with temperature is very non-linear.
Th i N Li i
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Thermistor Non-Linearity
Temperature Measurement
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Thermocouple, some more basics
How it works: Made up of two different
metals joined at one endto produce a small voltageat a given temperature.
Make up: Made of up two different
metals. Ex: A type J ismade up of Iron andConstantan.
Temperature Range Type J: 0 C to 750 C
A few Thermocouples
Temperature Measurement
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Thermocouple Advantages and Disadvantages
Advantages:
Self Powered (doesnot require a current
or voltage source) Rugged
Inexpensive
Simple
Disadvantages:
Extremely LowVoltage output (mV)
Not very stable Needs a reference
point
Temperature Measurement
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49K
1K
1K
50K
1K
1K
50K
50K
-Vin+
+-
+-
+
-
+Vout
-
+
-Thermocouple
4.7 F
7417
1 2
5V 15V
Fan
Relay
A Case Study
Temperature Measurement
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Thermocouples
Seebeck effect
If two wires of dissimilar metals are joined at bothends and one end is heated, current will flow.
If the circuit is broken, there will be an open circuitvoltage across the wires.
Voltage is a function of temperature and metal types.
For small DTs, the relationship with temperature islinear
For larger DTs, non -linearities may occur.
Measuring the Thermocouple Voltage
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If you attach the thermocouple directly to a voltmeter, you will haveproblems.
You have just created another junction! Your displayed voltage will beproportional to the difference between J 1 and J 2 (and hence T 1 andT2). Note: It is a Type T thermocouple.
External Reference Junction
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External Reference Junction
A solution is to put J 2 in an ice-bath; then you know T 2,and your output voltage will be proportional to T 1-T2.
Other types of thermocouples
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Many thermocouples dont have one copper wire. Shownbelow is a Type J thermocouple.
If the two terminals arent at the same temperature, thisalso creates an error.
Isothermal Block
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The block is an electrical insulator but good heatconductor. This way the voltages for J 3 and J 4 cancel out.Thermocouple data acquisition set-ups include theseisothermal blocks.
If we eliminate the ice-bath, then the isothermal blocktemperature is our reference temperature
1 block V T T
Software Compensation
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How can one find the temperature of the block? Use athermister or RTD.
Once the temperature is known, the voltage associatedwith that temperature can be subtracted off.Then why use thermocouples at all?
Thermocouples are cheaper, smaller, more flexible andrugged, and operate over a wider temperature range.
Most data acquisition systems have softwarecompensation built in. To use industrial automationsoftware, youll need to know if you have a thermister or
RTD.
Hardware Compensation
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With hardware compensation, the temperature of the
isothermal block again is measured, and then a battery isused to cancel out the voltage of the reference junction.
This is also called an electronic ice point reference . With
this reference, you can use a normal voltmeter instead of a thermocouple reader. You need a separate ice-pointreference for every type of thermocouple.
Potential Problems
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Poor bead construction Weld changed material characteristics because the weld temp.
was too high. Large solder bead with temperature gradient across it
Decalibration If thermocouples are used for very high or cold temperatures,
wire properties can change due to diffusion of insulation oratmosphere particles into the wire, cold-working, or annealing.
Inhomogeneities in the wire; these are especially bad in areaswith large temperature gradients; esp. common in iron. Metallicsleeving can help reduce their effect on the final temperaturereading.
Potential Problems
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Shunt impedance As temperature goes up, the resistance of many insulation types
goes down. At high enough temperatures, this creates a virtual junction. This is especially problematic for small diameter wires.
Galvanic Action The dyes in some insulations form an electrolyte in the water.
This creates a galvanic action with a resulting emf potentiallymany times that of the thermocouple. Use an appropriate shieldfor a wet environment. T Type thermocouples have less of aproblem with this.
Potential Problems
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Shunt impedance As temperature goes up, the resistance of many insulation types
goes down. At high enough temperatures, this creates a virtual junction. This is especially problematic for small diameter wires.
Galvanic Action The dyes in some insulations form an electrolyte in the water.
This creates a galvanic action with a resulting emf potentiallymany times that of the thermocouple. Use an appropriate shieldfor a wet environment. T Type thermocouples have less of aproblem with this.
Potential Problems
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Conduction along the thermocouple wire In areas of large temperature gradient, heat can be conducted
along the thermocouple wire, changing the bead temperature. Small diameter wires conduct less of this heat. T-type thermocouples have more of a problem with this than
most other types since one of the leads is made of copper whichhas a high thermal conductivity.
Inaccurate ice-point
Infrared Thermometry
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Infrared thermometers measure the amount of radiation emitted by
an object.
Peak magnitude is often in the infrared region.
Surface emissivity must be known. This can add a lot of error.
Reflection from other objects can introduce error as well.
Surface whose temp youre measuring must fill the field of view of
your camera.
Benefits of Infrared Thermometry
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Can be used for Moving objects Non-contact applications
where sensors would affectresults or be difficult to
insert or conditions arehazardous
Large distances Very high temperatures
Non-Electronic Temperature Gages
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Crayons You can buy crayons with specified melting temperatures.Mark the surface, and when the mark melts, you know the
temperature at that time.
Lacquers Special lacquers are available that change from dull toglossy and transparent at a specified temperature. This is a type of phase change.
Pellets These change phase like crayons and lacquers but are larger.If the heating time is long, oxidation may obscure crayon marks.Pellets are also used as thermal fuses; they can be placed so thatwhen they melt, they release a circuit breaker.
Temperature sensitive labels These are nice because you can peelthem off when finished and place them in a log book.
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Liquid crystals They change color with temperature. If thecalibration is know, color can be determined very accurately using a
digital camera and appropriate image analysis software. This is used afair amount for research.
Naphthalene sublimation (to find h, not T) Make samples out of naphthalene and measure their mass change over a specified timeperiod. Use the heat and mass transfer analogy to back out h.
Temperature Controllers
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Consider the following when choosing a controller Type of temperature sensor (thermocouples and RTDs are common)
Number and type of outputs required (for example, turn on a heater,turn off a cooling system, sound an alarm)
Type of control algarithm (on/off, proportional, PID)
On/off controllers These are the simplest controllers. On above a certain setpoint, and off below a certain setpoint On/off differential used to prevent continuous cycling on and off. This type of controller cant be used for precise temperature control.
Often used for systems with a large thermal mass (wheretemperatures take a long time to change) and for alarms.
Choice Between RTDs, Thermocouples, ThermistersCost thermocouples are cheapest by far followed by RTDs
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Cost thermocouples are cheapest by far, followed by RTDs
Accuracy RTDs or Thermisters
Sensitivity Thermisters
Speed Thermisters
Stability at high temperatures not thermisters
Size thermocouples and thermisters can be made quite small
Temperature range thermocouples have the highest range,followed by RTDs
Ruggedness thermocouples are best if your system will be taking alot of abuse
Hydraulic Heads and Mechanical Vibration
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Velocity Head
Velocity head =
g = gravitational constant = 32.2 ft/s 2
when V is 5 ft/s, V 2/(2g) is only about 0.4 ft (usually negligible)
g V 22
Elevation Head
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Elevation Head
Elevation head (gravitational head) = Z
Height of water above some arbitrary reference point (datum)
Water at a higher elevation has more potential energy than water ata lower elevation
Pressure Head
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Pressure = force per unit area (e.g., pounds per square inch)
Pressure head = pressure per unit weight of water
h = P / h = pressure head , P = pressure
= weight of a unit volume of water
= 62.4 lb/ft 3 = 0.433 psi/ft
1/ = 2.31ft/psi
h = 2.31*P (P is in psi; h in ft)
Calculate P at the Bottom of a Column of Water
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When depth of 2 ft is consideredV = 2 ft3
W = 2 ft 3 * 62.4 lb/ft 3
= 124.8 lb
A = 144 in 2 P = W/A = 124.8lb / 144 in 2
= 0.866 lb/in 2 If depth is 1ft then
V = 1 ft3
W = 62.4lb
P = 62.4lb/144in 2 = 0.433lb/in 2
Calculate P at the Bottom of a Column of Water
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V = 2 ft3 W = 124.8 lbA = 2ft2 = 288 in 2
P = 124.8lb / 288in2
= 0.433 lb/in 2
The area of a pond or tank does not affect pressure.
Pressure is a function of water depth only .
Manometer Rising up From a Pipeline
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Pressure, P = lb/ft 2 = specific weight of water, (62.4 lb/ft 3)
2
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hydraulic head, H =
Bernoullis equation (conservation of energy)
H1 = H2 + hL
H1 = hydraulic head at point 1 in a system H2 = hydraulic head at point 2 in a system
hL= head loss during flow from point 1 topoint 2 (h L is due to friction loss)
h Z
g
V
2
2
Components of Hydraulic Head for Pipeline With Various Orientations
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Components of Hydraulic Head for Pipeline With Various Orientations Contd
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Components of Hydraulic Head for Pipeline With Various Orientations Contd
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Friction Loss
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Description: energy loss due to flow resistance as a fluid moves in a
pipeline Factors affecting
flow rate pipe diameter pipe length pipe roughness type of fluid
Ways of Calculating Friction Loss
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Tables
for a given pipe material, pipe diameter, and flow rate,look up values for friction loss in feet per hundred feetof pipe
SDR = standard dimension ratio= pipe diameter wall thickness
What is Vibration?
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Scientific Definition
Engineering Definition
Any motion that repeats itself after an interval of time
Deals with the relationship between forces andoscillatory motion of mechanical systems
Basic Concepts
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Every object has:
Frequencies at which it likes to vibrate
Characteristic geometries of vibration
Every object has:
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Natural
Frequencies
1 24 34
Mode
Shapes
1 24 4 4 34 4 4
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Every object has:
Frequencies at which it likes to vibrate
Characteristic geometries of vibration
Modeling Vibration
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The Ingredients:1. Inertia (stores kinetic energy)2. Elasticity (stores potential energy)
1
Realistic Addition:3. Energy Dissipation
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The Ingredients:1. Inertia (stores kinetic energy)
2. Elasticity (stores potentialenergy)
1
Realistic Addition:3. Energy Dissipation
2
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The Ingredients:1. Inertia (stores kinetic energy)
2. Elasticity (stores potentialenergy)
1
Realistic Addition:
3. Energy Dissipation3
2
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The Ingredients:1. Inertia (stores kinetic energy)
2. Elasticity (stores potentialenergy)
2 3
1
Realistic Addition:3. Energy Dissipation
Modeling Vibration
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The Ingredients:1. Mass, m
2. Stiffness, k k c
m
Realistic Addition:
3. Damping, c
x
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How is thismodel useful?k c
m
x
Basic Concepts
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A vibration of large amplitude
Occurs when an object is forced near its naturalfrequency
Resonance
ResonanceA vibration of large amplitude
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A vibration of large amplitudeOccurs when an object is forced near itsnatural frequency
m
ck
x
t
M
e
Object Model
Vibration AbsorbersUsed to eliminate vibration of an object
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j
Object
VibrationAbsorber
(that vibrates toomuch)
(absorbsvibration)
Used to eliminate vibration of an object
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Used to eliminate vibration of an object
Object
VibrationAbsorber
(that vibrates toomuch)
Choose these toeliminate motion
of object.
Vibration Absorbers
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Temperature ScannersUltrasonic Signal
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SEAL
Transmitter Receiver
g
Pouch seal or packagematerial is placed betweenultrasonic transmitter andreceiver
Ultrasonic Signal
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Ultrasonic waves propagatethrough single or multiple layers of well bonded materials.
Transition through differentmediums causes reflection of soundwaves and reduces/eliminates signalstrength.
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Ultrasonic signal is transmitted along the X-axis through seal and signal isrecorded.
Signal measurement correlates to color gauge, creating high resolution image of seal structure and quality.
Opto Acoustic Image
Th l d h i l
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The colored gauge represents the scan signal measurement.
Pink is low signal, green is normal signal (good seal), purple is highsignal.
Total 6000 grades of color are used.
Scanning Modes
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C-Scan produces an
Opto -Acoustic imageand summary data
L-Scan produces agraph of the signaland summary data.
Pass Fail Criteria and Data Integrity
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Pass Fail limits are set for theaverage, minimum, maximum,and standard deviation of thesignal measurements,
All results are recorded usingthe systems data log.
Offline Analytical Equipment
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C-Scan Analytical Tools
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C-Scan window statistics
Modified L-Scan
10 mm
135 mm 128 mm
6 mm 3.5 mm
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105 C HDPE 105 C HDPE 105 C HDPE 105 C HDPE 105 C HDPE
128 C HDPE 128 C HDPE 128 C HDPE 128 C HDPE 128 C HDPE
108 C TYVEK 108 C TYVEK 108 C TYVEK 108 C TYVEK 108 C TYVEK
134 C TYVEK 134 C TYVEK 134 C TYVEK 134 C TYVEK 134 C TYVEK
Audibility of alarm systems
Alarm annunciators
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Sound patterns of alert signals shall be significantly differentfrom the temporal patterns of alarm signals .
Alarm signals shall conform to the temporal pattern defined
in the International Standard ISO 8201 (T3 signal)
Lower wiring costs
Con entional AddressableVS
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Conven
tionalFirePanel
Conventional AddressableVS
MS-9050UD
Single SLC Simplifies System Design
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HVAC Elevator Control
Intelligent Detectors
R i h f i
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Rotary switches for settingaddress 00-99
Easy to set in field withscrewdriver
No programming toolsrequired
Easy to identify address
Conventional Wiring
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Class B wiring incorporates end of line devices. (2 conductorcircuit)
Class A wiring does not incorporate end of line devices. (4conductor circuit)
T tap splices can not be used on either wiring method.
Class B Wiring
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Class A Wiring
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Th i l i i i h i b f d f Cl B
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The signal circuits in the suites can be feed from a Class B orClass A signal circuit isolators located outside the suite or;
Each suite can be feed from a separate signal circuit withoutthe need for a signal circuit isolator.
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Addressable System
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CPU
EOL
Sa Ha Ha
DATA COMMUNICATION LINK
ADDRESSABLE INPUT DEVICES
BELLS OUTPUT DEVICES
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Thank you