Present Ion on Ak

8/6/2019 Present Ion on Ak

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Temperature Sensor Types

Big differences exist between different temperature sensor or

temperature measurement device types. Using one perspective, they can be simply classified

into two groups.

C

ontact. Non-contact.

Both contact and non-contact sensors require some assumptions and

inferences in use to measure temperature.

Contact Type Temperature Sensors

Thermistors

Thermal resistors

Thermistors are special solid temperature sensors that behave like temperature-

sensitive electrical resistors

There are basically two broad types.

NTC-Negative Temperature Coefficient, used mostly in temperature sensing.

ANTC thermistor is one in which the zero-power resistance decreases with an

increase in temperature.

PTC-Positive Temperature Coefficient, used mostly in electric current control.

APTC thermistor is one in which the zero-power resistance increases with an

increase in temperature.

During the last 60 years or so, only ceramic materials (a mix of different metal oxides)

was employed for production ofNTC thermistors.

In 2003, AdSem, Inc. (Palo Alto, CA) developed and started manufacturing of Si and Ge

high temperature NTC thermistors with better performance than any ceramic NTC

thermistors.

NTCThermistor Probe Assemblies

NTC Surface Temperature Probes.


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NTCAir-Gas Temperature Probes.

NTC Liquid Temperature Probes.

Patient Temperature Monitoring Probes.

NTC HVAC-R Temperature Probes.

Nickel RTD SMD Sensors

Precision NTCThermistor Thermometers

Model System Accuracy Application

4600 High Accuracy 0.115C from 0C to 50Cwhen used with 400-seriesprobes

Laboratory measurements

4600S TransferStandard

0.025C from 0C to 50C w/dedicated probe and 4-ptcalibration

Near metrology levelmeasurements

4610 High AccuracyInterchangeable

0.05C from 20C to 50C w/4610-series probes

Precision measurementswithin the biologicaltemperature range

NTC Resistance Temperature Characteristic Formula:

The resistance of a thermistor is solely a function of its absolute body temperature. When testingfor resistance accuracy it is essential that the surrounding environmental temperature is held ata constant, and power dissipated in the thermistor is low enough to insure no "self-heating".

Formula for determining resistance of RTI compositionA, B, C and E NTC thermistors at anytemperature within the operating limits:

Where:

is the resistance at Temperature T

is the resistance at 25C

is 2.718

is the Temperature at which R is unknown expressed in Kelvin. (273.15 + C)

is 298.15K (25C)

is (a + bT+ cT2)

Comp. A Comp. B Comp. C Comp. E

a = 2641.67 2183.03 2923.94 3197.35

b = 1.0643 6.619 4.8657 4.2865

c = -0.0001571 -0.008048 -0.005363 -0.001836

The temperature coefficient of resistance ( ) is expressed mathematically as follows:


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which is approximately equal to /T2

NTC APPLICATIONS

Temperature Measurement. Temperature Differential. Temperature Control. Temperature Compensation. Time Delay. Surge Suppression.

Temperature Differential:

By placing matched thermistors in two legs of a bridge circuit as seen in Figure, temperaturedifferentials as close as .001C can be readily detected.

TemperatureControl:

By placing a thermistor in series with a relay coil and potentiometer as shown in Fig, a simpletemperature controller is obtained. The potentiometer will control the switching temperature.

A more sensitive controller can be obtained by feeding the output of a thermistor bridge asshown in Figure into a high gain amplifier. Sensitivity of .005C can be sensed easily with thismethod.

TemperatureCompensation:


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Since all metals used for coil windings, etc., have a positive temperature coefficient ofresistance, NTC thermistors are especially useful for compensating resistance changes indevices subjected to temperature variations. Where a copper meter coil would change 50% inresistance over a commonly used temperature range, a thermistor shunted by a resistor inseries with the unit as shown in Figure 5 allows the total impedance of a circuit to be helduniform over the entire operating range. Due to the high temperature coefficient of the

thermistor as opposed to the low temperature coefficient of the copper, full compensation canbe achieved by using a thermistor- resistor network. This network adds less than 15% to thetotal impedance of the circuit. Compensation of transistor amplifiers, crystal oscillators, etc.can be achieved by using similar methods.

Time Delay:

By placing a thermistor in series with a relay, a potentiometer, and a battery as shown inFigure 4, a simple time delay circuit is obtained. A relatively high potential is applied to thecircuit. The thermistor begins to "self-heat," lowering its resistance and allowing more currentto flow. The increased current further heats the thermistor, allowing still more current to flow,which in turn actuates the relay. The time required for the relay to actuate after voltage isapplied can be controlled by adjusting the potentiometer.

Surge Suppression:

By placing a thermistor in series with a filament string as shown in Figure 6, current surge canbe eliminated. The resistance of the thermistor is higher than the total resistance of thefilaments when the circuit is turned on. As current begins flowing, the thermistor "self-heats."Its resistance is reduced to a minimum and becomes insignificant to the total resistance of acircuit.

Current surges in electric motors can be held to minimum using the same concept. Figureshows a typical DC motor's turn-on surge before and after the application of a RTI thermistorto the circuit.


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Thermocouples (TCs)

Thermocouples are pairs of dissimilar metal wires joined at least at one end, which

generate a net thermoelectric voltage between the the open pair according to the size of the

temperature difference between the ends, the relative Seebeck coefficient of the wire pair and

the uniformity of the wire-pair relative Seebeck coefficient.

They are based on the Seebeck effect that occurs in electrical conductors thatexperience a temperature gradient along their length.

EMF-Temperature tables can only be used when the circuit consists of only twowires,both of which are uniform in calibration, and both of which begin at TRefand end at TJct.When only small temperature differences areinvolved, the values of Aand B can betreated asconstants, and Eq. 4 gives a good approximation to the EMF.

Thermocouple Materials

The three most common thermocouple alloys for moderatetemperatures areIron-Constantan (Type J), Copper-Constantan (Type T), and Chromel-Alumel (TypeK).

The first named element of the pair is the positive element. The negative wire is color coded red (current U.S. standards).

A circuit of single thermocouple.

Thermocouples can be connected in series with one another as given circuit.


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Measuring Differences:The temperature difference between two point scan be directly

measured by connecting the two negative wires together (at room temperature) andmeasuring between the two positive wires. The magnitude gives the temperaturedifference, and the positive wire is connected to the hotter of the two locations. Thisapproach offers no advantage in accuracy over reading the two thermocouples

separately and subtracting the temperatures.

o One pair is used as a thermocouple to determine the temperaturelevel, and one pair is used to determine the temperature differencebetween two points.

Subject Matter:

There are about three or four "classes"of thermocouples. Although no one really calls themclasses, they really are.

There are:

1. The home body class (called base metal),2. the upper crust class (called rare metal or precious metal),3. the rarified class (refractory metals) and,4. the exotic class (standards and developmental devices).

In most countires all but the most exotic class are codified by a letter designation.

The home bodies, at least in the USA, are the Types E, J, K, N and T.

The upper crust are: types B, S, and R, platinum all to varying percentages .


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The exotic class includes several tungsten alloy thermocouples usually designated as Type W(something).

Specifications:

Thermocouple Type J, K, or N

Standard Limits of Error +/- 2.2Cor 0.75% (which ever is greater)

Thermocouple Type TStandard Limits of Error +/- 1.0Cor 0.75% (which ever is greater)

Thermocouple Type EStandard Limits of Error +/- 1.7Cor 0.50% (which ever is greater)

Thermocouple Type R or SStandard Limits of Error +/- 1.5C

or 0.25% (which ever is greater)

Thermocouple Type BStandard Limits of Error +/- 0.50%

Thermocouple Temperature Sensor Applications:

Thermocouples are used in many places with many things like indicators andcontrollers to do something useful, such as control a heating system to heat a product througha temperature-time profile that causes it to soften or cook or set or transform from a stressedcondition to an annealed one or any number of physio-chemical changes that produce adesired end result.

Liquid In Glass Thermometers

Liquid in glass thermometers are the sensor one visualizes most often for temperaturemeasurement.

A glass cylinder with a bulb at one end, a capillary hole down the axis, connected to the

reservoir in the bulb filled with silvery mercury or perhaps a red-colored fluid, anengraved temperature scale.

The thermometer that checked your fever when you were young was a specializedversion of this oldest and most familiar temperature sensor.


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Applications:

Glass thermometers are among the oldest and still the most widely type of

thermometer used in laboratory work and in households

Medical Sciences

To determine fever temperature in humans.

Resistance Temperature

Detectors (RTDs)

Resistance Temperature Detectors or RTDs for short, are wire wound and thin filmdevices that measure temperature.

It measures temperature because of the physical principle of the positive temperaturecoefficient of electrical resistance of metals.

The hotter they become, the larger or higher the value of their electrical resistance. They, in the case ofPlatinum known variously as PRTs and PRT100s, are the most

popular RTD type. They are among the most precise temperature sensors available with resolution and

measurement uncertainties or 0.1 C.

The Advantages of RTDs

The advantages of RTDs includes:

Stable output for long period of time. Ease of recalibration. Accurate readings over relatively narrow temperature spans. Their disadvantages, compared to the thermocouples, are: smaller overall temperature

range, higher initial cost and less rugged in high vibration environments.


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They are active devices requiring an electrical current to produce a voltagedrop across the sensor that can be then measured by a calibrated read-out device.

RTD Error Sources

The lead wires used to connect the RTD to a readout can contribute to theirmeasurement error, especially when there are long lead lengths involved.

Often the lead error can be minimized through use of a temperature transmittermounted close to the RTD.

RTDs, as mentioned , work in a relatively small temperature domain, compared tothermocouples, typically from about -200 C to a practical maximum of about 650 to700 C.

Insulation resistance is always a function of temperature and at relatively hightemperature the shunt resistance of the insulator introduces errors into measurement.

Standard Platinum RTDs(SPRTs)

P

latinum is the preferred material for precision measurementbecause in its pure form the Temperature Coefficient of Resistance is nearly linear; enough sothat temperature measurements with precision of 0.1 C can be readily achieved. All RTDsused in precise temperature measurements are made ofPlatinum and they are sometimescalled PRTs to distinguish them.

According to ITS-90 (International Temperature Scale of 1990- used as a worldwidepractical temperature scale in national metrology labs like NIST, NPL et al) A specialset ofPRTs, called SPRTs, are used to perform the interpolation in such labs over theranges 13.8033 K (Triple point of Equilibrium Hydrogen) to the Freezing point of Silver,971.78 C.

Platinum RTD Output Equation:

1. Platinum Resistance Thermometers specifies that the resistance-temperature

relationship for such devices for the range 0 C to 650C, to within the tolerances given

below, will be described by the equation:

R(t) = R(0)[1 + At +Bt^2]

Where:

t = temperature (to ITS-90), C,

R(t) = resistance at temperature t,

R(0) = resistance at 0C

A = 3.9083 * 10^-3(C), and,

B = -5.775 * 10^-7(C^2).

More details and the equation for -200 C to 0C as well as the inverse, temperature as

a function of resistance are provided in the standard.


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y The Callendar-Van Duson equation and others are used to correct for the

nonlinearity of the resistance-temperature relationship for very high

accuracy measurements, such as those performed in a metrology or

calibration laboratory .

Recommended Use Limits and Tolerances:

1. "Standards Specification for Industrial Platinum Resistance Thermometers" gives many

details and specifications for them over the range from -200 C to 650C.

It defines two RTD grades, A and B with a resistance-temperature relationship that has

the following tolerances:

Grade ATolerance = [0.13 +0.0017 *|t|] C

Grade B tolerance =[0.25 +0.0042 *|t|] C

where |t| is the absolute value of the RTD's temperature in C.

1.

RTD Classifications And ToleranceLimits per ASTM E1137

Temperature

Degrees C

Grade A

Limits

Grade B

Limits

C Ohms C Ohms

-200 0.47 0.20 1.1 0.47

0 0.13 0.05 0.25 0.10

100 0.30 0.11 0.67 0.25

400 0.81 0.28 1.9 0.66

650 1.24 0.40 3.0 0.94

2. The DIN Standard recognizes three different tolerance classes, they are:

DINClass A tolerance: [0.15 + 0.002*|t|] C

DINClass B tolerance: [0.30 + 0.005*|t|] C

DINClass C tolerance: [1.20 + 0.005*|t|] C.


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Figures: Resistance Temperature Detectors


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Filled System Thermometers

Filled System, or just filled thermometers are those that work on pressure or volume

change of a gas or changes in vapor pressure of a liquid.

The gas or gas and liquid are contained usually in a sealed metal tubing and bulb

system.

The filled thermal device consists of a primary element that takes the form

of a reservoir or bulb, a flexible capillary tube, and a hollow Bourdon tube

that actuates a signal-transmitting device and/or a local indicating temperature

dial.

In this system, the filling fluid, either liquid or gas, expands as temperature

increases.

This causes the Bourdon tube to uncoil and indicate the

temperature on a calibrated dial.

The filling or transmitting medium is a vapor, a gas, mercury, or anotherliquid.

The liquid-filled system is the most common because it requires a

bulb with the smallest volume or permits a smaller instrument to be used. The gas-filled system uses the perfect gas law, which states the following

for an ideal gas:

T= kPV


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where:

T = temperature

k = constant

P = pressure

V = volume

If the volume of gas in the measuring instrument is kept constant, then theratio of the gas pressure and temperature is constant, so that

The only restrictions on above Equation are that the temperature must beexpressed in degrees Kelvin and the pressure must be in absolute.

Accuracy:+/- 1 % of full scale. Calibration to NIST traceable standards.

Ranges:TwentyF and F & C ranges available from -320F to 1200F. Overrange:Minimum 50% of span above top of range, or 1300F, whichever is less. Ambient Error: 1/4% of span per 25F change in ambient temperature at midscale.

Dial Sizes:41/2& 6. Dials are white with black markings.

Case Materials:Stainless steel, Phenolic, or Aluminum.

Case Styles:Panel Mount, Surface Mount, or Direct (stem) Mount.

Windows:Glass is standard. Shatterproof glass and acrylic are optional.

Pointers: Slotted adjustable type to permit zero set adjustments.

Bulbs:316 Stainless Steel, 3/8 dia. x 3 active length.Other diameters and lengths are also available.

Process Connections:Plain bulb; 1/2 NPT sliding union; 1/2 NPTfi xed (on All-Angle); or thermowell.

Note: Thermowells should be used whenever the bulb would be exposed to pressure, fl uid velocity, or corrosive or abrasive media.

Thermal Systems:Stainless steel capillary with stainless steel spring armor (up to 40ft). Over 40 feet, stainless steel interlock armor is standard. Direct mount stems, 316 SS, 4 to 48.


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The gas types were used in many industrial applications and for establishing portions ofthe thermodynamic temperature scale.

They can be very simple, non-powered devices with great reliability and repeatability. The vapor pressure types have a bulb, the sensing portion, filled with a volitile liquid,

instead of a gas. Since they are more sensitive to temperature changes than a gas type. They can be physically smaller, however their relative temperature measurement span

is quite a bit smaller.


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Bimetallic Thermometers and Thermostats

The simple mechanical sensor that works in most "old-fashioned" thermostats based onthe fact that two metals expand at different rates as a function of temperature.

They're the coil of metal that has some electrical contacts affixed to it. For correct temperature measurement, the stem of all models in all ranges must be

immersed 2 inches in liquid, and 4 inches in gas.

Specifications - Bimetallic Thermometers

Dial Sizes: 1 1/8", 1 3/4 ", 2 3/8", 3", 4",5".Stem Length: Between 2" and 80".Stem Diameters: 1/4 " (standard), alsoavailable 5/16", 3/8".Heads, bezels, mounting bushing,stems:All Models 300 Series SS.Operating Conditions:The temperature of

the head should not be allowed to exceed200F (150F if silicone filled). Stems shouldnot be exposed to continuous temperaturesexceeding 50% over-range, or 800F.Hermetic seal : All 3", 4", and 5" models(except DM4) are hermetically sealed perASME B40.3.Pointed Stems:Optional on all models.Excellent for probing asphalt, compost,soil, frozen foods or other semi-solidmaterials.

Crystals:Optically clear strong glass. Optional:Unbreakable clear plastic: all models (Notrecommended for ranges over 500F). Optional:"Shatterproof" tempered glass (3", 4", and 5"models).Accuracy:All models are guaranteed accurate towithin plus or minus 1% of the full scale (GradeA per ASME B40.3). Temperature readings arestabilized within 40 seconds.Immersion: For correct temperaturemeasurement, the stem of all models in allranges must be immersed 2 inches in liquid, and4 inches in gas except for 0 to 100F, 25 to 125F,and 0 to 50C which require 3 1/2 inches inliquid and 5 inches in gas.Mounting Connections: 1/2" NPT(std. on 3", 4",5" models), 1/8" NPT, 1/4 " NPT, 3/8" NPT, 3/4 "NPT, 3/8"-24" NF, Plain or Reset Bushing, 1/2 "NPTUnion, 1/2 " BSPT, BSPPAdapters.

.

Bimetallic thermometers are contact temperature sensors found in severalforms, e.g. inside simple home heating system thermostats.

They are more familiar to many people in industry and commerce asminiature pocket dial thermometers that many people use to check thetemperature of fat in a deep frier or a vat on a small process line.

The major uses are where a quick check of the temperature of an object isdesired.


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Semiconductor Thermometer Devices

AKA Diodes & Integrated Circuit (IC) Temperature Sensors

Prologue:

Semiconductor thermometers are usually produced in the form ofICs,Integrated Circuits.

Most are quite small and their fundamental design results from the fact thatsemiconductor diodes have voltage-current characteristics that are temperaturesensitive.

Semiconductor triodes or transistors are also temperature sensitive. there devices have temperature measurement ranges that are small compared to

thermocouples and RTDs.

They can be quite accurate and inexpensive and very easy to interfacewith other electronics for display and control.

Semiconductor technology enables devices to be produced efficiently andcheaply and to have properties designed to easily interface with manyother types of semiconductor devices, such as amplifiers, powerregulators, buffer output amplifiers and, least we forget, microcomputers.

The major uses are where the temperature range is limited to within a

minimum temperature of about -25C

to a maximum of about 200C

.simplicity of interfacing with other circuit elements and size are factorsin selecting a device to do a job and meet the both the accuracy and costbudgets.

Simplicity of interfacing with other circuit elements and size are factorsin selecting a device to do a job and meet the both the accuracy and costbudgets.


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Figures: Semiconductor ThermometerDevices


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Non-Contact Type Temperature Sensors

Radiation Thermometers

Prologue:

Radiation Thermometers (Pyrometers, if you will) are non-contact temperature sensorsthat measure temperature from the amount of thermal electromagnetic radiationreceived from a spot on the object of measurement.

In addition to line measuring radiation thermometers, which produce 1-D and, withknown relative motion, can produce 2-D temperature distributions, and thermalimaging, or area measuring, thermometers which measure over an area from which theresulting image can be displayed as a 2-D temperature map of the region viewed.

They are used widely in many manufacturing process like metals, glass, cement,ceramics, semiconductors, plastics, paper, textiles, coatings, and more.

They enable automation and feedback control that boost productivity while improving

yield and product quality. In reliability and maintenance needs from building heating to electrical power

generation and distribution, they save downtime and help optimize practices. The physics behind that broadcasting is called Planck's Law ofThermal Radiation.

APPLICATIONS ARE WHERE THE SENSORS MEET THE "REAL WORLD"; WHERE THE RESULTS PROVE THAT YOU

UNDERSTAND THEIR USE AND HAVE SELECTED WELL ENOUGH TO DO THE JOB!

They save lives and improve safety in fire-fighting, rescues, and detection of criminalactivities.

In hospitals, nursing homes and home care, they have enabled a new , quick and

reliable method to monitor and measure human body temperatures with one secondtime response.

In reliability and maintenance needs from building heating to electrical powergeneration and distribution, they save downtime and help optimize practices.

Figures: Radiation Thermometer


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Prologue:

o High Temperature Infrared Thermometero AutomaticallyCorrects For Emissivityo AccuracyAfter EmissivityCorrection: 5F ( 3C)o 1msData Acquisition Rateo Standard Temperature Ranges:o 1100F - 2730F (600C - 1500C)o Extended Temperature Ranges:

1300F - 3600F (700C - 2000C)1450F - 4500F (790C - 2500C)

1550F - 5400F (850C

- 3000C

)o Internal Data Notebook & PCInterface

Classification - temperature measurement, high temperature sensor, non contactinfrared thermometer.

The Pyrometer portable infrared thermometer


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The Pyrometer portable infrared thermometer uses the latest pulsed laser technology toprecisely measure the true target non contact temperature measurement.

All non contact infrared thermometer instruments measure a target radiancetemperature; it dynamically determines a targets emissivity value resulting inunmatched temperature accuracy to 3 C.

The Pyrolaser incorporates an electronic microprocessor control unit, LCD digitaldisplay, membrane keypad, power supply, and temperature measurement outputconnections and precision glass optics.

The Pyrolaser's microprocessor control measures radiance, emissivity, andbackground radiance values at an extremely fast 1ms data acquisition rate.

The Pyrolaser automatic emissivity correcting IR thermometer is used for manyindustrial and laboratory applications.

This includes temperature measurement in refractories, ovens, furnaces andvacuum chambers. Virtually anywhere accurate portable IR temperaturemeasurements are required.

y Petroleum Furnace Tube Temperatures

y RefractoryTemperature Measurementy Production Steel Annealing Furnaces

y Production Copper Furnaces

y Induction Heatingy Ceramic & Graphite Production

Selectable Readout: F,C

Standard Temperature Range: 1100F - 2730F (600C - 1500C)

Optional Extended Temperature Ranges:

See Calibration Lens & Filter Table Below)

1300F - 3600F (700C - 2000C)

1450F - 4500F (790C - 2500C)

1550F - 5400F (850C - 3000C)

Calibration Ranges: (4) Ranges Available

Accuracy: 5F (3C)

Resolution: 1F (1C)

Repeatability: 1F (1C)

Effective Wavelength: 0.905 m 0.015


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Bandwidth: 0.055 m

Automatic Emissivity Measuring Range: 0.01 -1.0 ( Increments 0.01 )

Acquisition Time: 1ms - 2000ms Selectable

LED Display In Viewfinder: 4 Digit Corrected Temperature (Tt)

LCD Display 40 Digit Readout of Target Distance Emissivity Value (E), UncorrectedTemperature (Tu), & Corrected Temperature (Tt)

Standard Target Distance:

Optional Target Distances AvailableSee Calibration Lens & Filter Table Below

2-10 meters

Target Size vs. Distance:

Standard 2 - 10 meter Range

Optional Target Size/Distances AvailableSee Calibration Lens & Filter Table Below

Target Size Target Distance

(Target Size = 1/200 of Target Distance)

Min Max Min Max

0.39" (5cm) 1.96" ( 5cm) 6.56' (2m) 32.8' (10m)

Visual Field Of View: 7

IR Field Of View: 0.333 (1mm @ 20cm; 0.04" @ 8")

Sample Rate 1, 2, 4, 8, 21, 23, 37 Readings/sec Selectable

Maximum Equipment Operating Temperatures: 32F - 90F (0C - 32C)

Display Output: LCD 3.5" x 0.75"

Target Emissivity

Target Uncorrected Temperature

Target Emissivity Corrected Temperature

Instrument Enclosure: Cast Aluminum

Auxiliary Output: Single Analog Output: 0 -5vdc or 0-20mA

Single Digital Output : RS232C

Power Supply: (3) x 9v Rechargeable Ni Cad Batteries

115v/60Hz or 230v/50Hz Charger

2 Hours Operating Time w/Batteries - Unlimited Operating Time WithCharger.


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Prologue:

y Optical Sensor Radiation Pyrometery Rugged Lightweight Portable

y Six Models Availabley Accuracy 0.5% of Reading

y Single Double & Triple Temperature Ranges1420F - 5800F (770C - 3200C)

y Target Sizes to 0.055" (1.4mm), Small Target

y Target Distance 12" to Infinity .

Classification- Optical sensor, non contact high temperature measurement,radiation pyrometer.

The PYROOptical pyrometer temperature sensor for non contact high temperature

measurement operates by allowing the operator to compare the intensity of light

radiated from a target at visible .655 m wavelength to the known brightness of an

internal calibrated lamp.

This is achieved by utilizing a rotating optical photoscreenic wedge that functions as a

variable neutral density filter.

. The PYROOptical pyrometer can achieve temperature measurement accuracy to

0.5% of the temperature being observed.

The PYROOptical radiation pyrometer is used for many industrial applications

to measure non contact high temperature measurements.

The optical sensor red scales can be provided for emissivity correction of targets with a 0 .4 emissivityvalue.

This is useful for temperature measurement of molten iron & steel.


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The PYROOptical pyrometer is calibrated at an effective wavelength of0.655

m and is inherently less subject to most errors due to uncertainemissivity or extraneous reflected light than infrared or radiationthermometers.

y Molten Metals

y Forgingy Refractories

y Ceramics

y Investment Castingy Calibration Procedures

The schematic drawing above illustrates the PYROOptical Pyrometer optical andelectrical system. The instrument optics serve as a telescope. The PYROOptical's lenses and

prisms provide a clear, enlarged view of the target.

Model Number Type Min Target Size Temperature Range F Temperature Range C

81F or 81C Single Range .090" (2.2mm) 1420F - 2500F 770C - 1400C

82F or 82C Single Range .090" (2.2mm) 1800F - 3400F 1000C - 1900C

83F or 83C Double Range .055" (1.39mm)1420F - 2200F 770C - 1200C

1800F - 3400F 1000C - 1900C

84F or 84CFoundry Type w/ *Red

Scale.055" (1.39mm)

1800F - 3400F 1000C - 1900C

2200F - 3700F 1200C - 2000C

85F or 85CTriple Range w/ *Red

Scale.055" (1.39mm)

1420F - 2200F 770C - 1200C

1800F - 3400F 1000C - 1900C

2200F - 3700F 1200C - 2000C

87F or 87C Triple Range .055" (1.39mm)

1420F - 2200F 770C - 1200C

1800F - 3400F 1000C - 1900C

3200F - 5800F 1800C - 3200C


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*Note: Red scales feature temperature readings corrected for materials with an emissivityvalue of 0.4.Red scales are typically used for measuring the temperature of molten iron and steel.

Optional high temperature filters are available to extend temperature ranges to 7700F or4500C.

Prologue:

y Temperature sensor probe, 4 Application Models

y Temperature Range: 32F - 2462F (0C - 1350C)y Accuracy: 0.3% Readingy Large LCDDisplay, Selectable F or Cy Records Min/Max, Hold

y Automatic Cold End Junction Compensationy Durable Housing with Boot

y Lightweight Compact Designy Standard 9 volt battery

y Low Battery Warning Displayy Meter Three Year Warranty

Classification - Temperature Sensor Probe, Digital Thermometer, K typeThermocouple, manufacturer.

Figure: thermocouple thermometer


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The Pyrometer Digital 250 Series Model SDT141S digital thermometer models are a low cost, high accuracyflexible temperature measurement system.

These digital thermometer pyrometers are ideal for temperature measurement using thermocouple thermometer Ktype thermocouples.

Each thermocouple thermometer has high meter accuracy of +/- 0.

3% of reading.

The temperature is displayed in degrees F or C on a large 1/2" high LCD Display. The SDT-141S meter is enclosed by a standard rubber boot for shock absorption and features a rear stand for

desktop temperature reading applications.

The PYRO Digital 250 Series thermocouple thermometer models can accommodate a wide variety ofindustrial, commercial, laboratory and small business applications.. Each model has a wide range of selectable extensionarms, interchangeable thermocouples and tips that are suited for those specific applications.

y Foundriesy Castings

y Molten Coppery Molten Tiny Molten Brass

y Molten Bronzey Molten Aluminum

y Molten Zincy Rolling Millsy Heat Treating

y Rubber Processingy Billets

y Ceramicsy Rotating Rollsy Steam Traps

y Sheet Metaly HVAC

y Oven / Kilnsy Asphalt / Paving

Selectable Readout & Resolution:F or C , 1/10 from 0-999 and 1 over 1000 F or C

Temperature Range:

Type K: 32F - 2462F (0-1350C)

Type J: 32F - 1832F (0-1000C)

Accuracy: 0.3% Of Temperature Displayed

Ambient Temperature Range:40F to 120F (5C - 50C)

Digital Display:4 Digits - Characters 1/2" High

Cold Junction Compensation:Automatic

Power:9.0 Volt Alkaline Battery, 100 Hours Continuous Operation

Present Ion on Ak

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