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PE PRODUCTS IRt /c TRAINING. IRt/c Infrared Answers. TIME TO PUT ON YOUR THINKING CAPS. Bob Harris Industrial Sales/ Corporate Marketing Manager. Company Profile History of Infrared IR Theory The IRt/c. IRt/c Applications D Series Microscanner SnakeEye Thermal Switch Speed Boost.
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PE PRODUCTS IRt/c TRAINING IRt/c InfraredAnswers TIME TO PUT ON YOUR THINKING CAPS www.exergen.com
Bob HarrisIndustrial Sales/ Corporate Marketing Manager www.exergen.com
Company Profile History of Infrared IR Theory The IRt/c IRt/c Applications D Series Microscanner SnakeEye Thermal Switch Speed Boost AGENDA www.exergen.com
COMPANY PROFILE • Founded by Francesco Pompei in 1980 to develop new methods of reducing energy use • Mr. Pompei was hired by Harvard University to solve energy related problems and saved up to $10 million in its first years • The first pocket sized infrared scanners were developed to save energy • The first infrared sensor in history capable of providing a thermocouple signal measuring temperature, non contact, with no power source was developed • Medical infrared thermometers were developed and used at the Boston Marathon, Barcelona Olympic games, and Desert Shield www.exergen.com
Located in Watertown, MA Manufacturing over 1 million Consumer TemporalScanner Thermometers Hundreds of thousands of Professional TemporalScanner Thermometers Tens of thousands IRt/c’s www.exergen.com
HISTORY OF INFRARED • All objects emit infrared energy, at temperatures above absolute zero (-273°C, -460°F) • Sir William Herschel discovered infrared radiation by measuring the temperature of various colors separated by a prism. • Herschel accidentally placed his thermometer below the red region, and noted a further increase in temperature. • Herschel called this invisible light, infrared, which means below red. www.exergen.com
HISTORY OF INFRARED • The first non-contact thermometer was the human eye • Sight has been used for steel working, glass working, wax molding, and pottery www.exergen.com
q Wavelength Max Planck ~ 1900 • Desperation Move to Explain Black Body Radiation • Mathematical Equation for Thermal Radiation www.exergen.com
Albert Einstein ~ 1905 • Confirmed Planck’s Quanta by Explanation of Photoelectric Effect • But Never Really Liked the Eventual Result www.exergen.com
Dr. Francesco Pompei ~ Present • Invented the world’s first pocket sized scanner • Invented the world’s first Infrared thermocouple • Invented non invasive medical infrared thermometers • Introduced Speed Boost Equation www.exergen.com
INFRARED THEORY • Infrared radiation obeys many of the laws that apply to light • When infrared energy strikes an object it may be reflected from that surface, transmitted through the surface, or absorbed into that surface • The sum of the reflectivity plus absorptivity plus transmisivity equals one (1 =r+a+t) • When an object is at thermal equilibrium, the amount of absorption is equal to the the amount of emission (a=e) www.exergen.com
RAT Theory R = RELECTIVITY A = ABSORPTIVITY T = TRANSMISSION At thermal equilibrium Absorptivity = Emissivity www.exergen.com
Black Body • Ideal IR radiator or perfect emitter • Nothing can emit more energy at all wavelengths than a blackbody • Utopia - it doesn’t exist in the real world www.exergen.com
UNDERSTANDING EMISSIVITY • Emissivity characterizes an object’s ability to emit radiation • Objects with high emissivity radiate well • Objects with low emissivity radiate poorly www.exergen.com
Emissivity – Mathematically Definition - amount of energy an object emits compared to that of a black body at the same wavelength and temperature. e =real object emitted energy blackbody emitted energy Emissivity values range from 0 to 1 www.exergen.com
SOME EMISSIVITY VALUES www.exergen.com
MATERIAL PROPERTIES • HIGH EMISSIVITY TARGETS – Non metals, paper, rubber, plastic, water, etc. • LOW EMISSIVITY, HIGHLY REFLECTIVE TARGETS – Metals, metallic coatings, etc. • LOW EMISSIVITY, HIGHLY TRANSPARENT TARGETS – Thin films and plastics, semiconductors,etc. www.exergen.com
HIGH EMISSIVITY SURFACES PERFECT EMITTER Emissivity = 1.0 Reflectivity = 0.0 Transmission = 0.0 GOOD EMITTER Emissivity = 0.9 Reflectivity = 0.1 Transmission = 0.0 www.exergen.com
LOW EMISSIVITY, HIGHLY REFLECTIVE SURFACES METALS PERFECT REFLECTOR Emissivity = 0.0 Reflectivity = 1.0 Transmission = 0.0 POOR EMITTER Emissivity = 0.1 Reflectivity = 0.9 Transmission = 0.0 www.exergen.com
Low Emissivity, Highly Transparent Surfaces THIN FILMS, SEMICONDUCTORS & PLASTICS PERFECT TRANSMITTER Emissivity = 0.0 Reflectivity = 0.0 Transmission = 1.0 POOR EMITTER Emissivity = 0.1 Reflectivity = 0.0 Transmission = 0.9 www.exergen.com
Explain the hot spot?This can of suds is ice cold straight out of the fridge. When scanned with an infrared camera you would expect the entire image to be relatively even in temperature and to appear "cold" in relation to the background. Can you explain the apparent "hot" spot in the center of the can. Hint: it's not a fingerprint! www.exergen.com
Live image reveals truth. The curtain is lifted and the truth revealed. The paint on the outside of the can has been scratched off in a small area. The bare aluminum has a different emissivity than the painted aluminum. www.exergen.com
INFRARED DETECTORS • The main component in any infrared system is the detector • The detector converts radiant energy into an electrical signal that may be used to provide a variety of desired readouts • Thermal detectors • Thermocouple - two dissimilar metals are connected and heat is applied to one of the junctions, electrons flow through the circuit • Thermopile - A series of thermocouples is called a thermopile. Thermopiles generate larger voltage potentials, for a given temperature , than thermocouples www.exergen.com
Why use Infrared Sensors • Don’t wish to “damage” the product • Faster response time • Temperature range • Measures product temperature www.exergen.com
IRt/c Family www.exergen.com
IRt/c Inherent Characteristics • Self powered - no external power required • Emulates a thermocouple within 2% at range close to its calibration point • Calibrated on real world (greybody) targets, emissivity ~ 0.9 • Intrinsically safe • Small size, simple, rugged, low cost • Fast response time ( 80-120 msec) • Ambient temperature changes compensated for in linear range www.exergen.com
IRt/cPrinciples of Operation IRt/c: mVout = c (Tt-Ts)+ (Ts-Tcj) when c= , mVout = (Tt-Tcj) Conventional t/c: mVout = (Ts-Tcj) = Seebeck coefficient www.exergen.com
Rs R2 RT + Vs R3 V+ R1 C1 V- Simple elegant design for high reliability • Mathematical equations solved by drift free passive components • No power requirement • Capable of withstanding harsh environments over indefinite times delivering accuracy www.exergen.com
Field of View • The ratio of distance between target and sensor to the spot size. • Example: Distance between sensor and target = 5”, Spot size is 1” diameter, the field of view is 5:1. www.exergen.com
Optical Alignment • Target must be larger than spot size • Must have non-obstructed view • Inaccurate temperature readings will result if: • Target is too small compared to spot • Spot overlaps target • Sensor is “knocked” or misaligned www.exergen.com
IRt/c OUTPUT • Output emulates that of a standard t/c (J,K, etc.) within a specified temperature range • The output is a mV output signal • The signal is predictable and very repeatable • The units are calibrated on real world, gray body targets and ambient conditions for the highest accuracy • mV output tables for all precalibrated IRt/c’s are available so the end user can increase accuracy and expand linear range www.exergen.com
STANDARD RANGES PRECALIBRATED MODEL RANGE 50F/10C 0-85F (-18-30C) 80F/27C 32-120F (0-50C) 140F/60C 70-190F (20-90C) 180F/90C 140-220F (60-105C) 240F/120C 180-250F (80-120C) 280F/140C 240-330F (115-165C) 340F/170C 280-370F (140-190C) 440F/220C 320-500F (160-260C) www.exergen.com
mV Signal Output Table www.exergen.com
IRt/c-J-80F Signal Output 3.00 2.50 2.00 1.50 mV IRt/c 1.00 0.50 Type J thermocouple 0.00 0 20 40 60 80 100 F -0.50 -1.00 Temperature www.exergen.com
K type t/c www.exergen.com
IRt/c-K-80F vs K t/c www.exergen.com
Programmable Input Devices Incorporating the IRt/c Polynomials • Numerous OEM customers in custom controls, computer interfaces, & programmable transmitters • The purpose is to condition the IRt/c signal and make it easy to work with from a user standpoint • Increases the range of most IRt/c’s so that the any IRt/c can be used over a wide range (~ -50 –1200F) www.exergen.com
Ambient temperature limits by model • IRt/c.01 and IRt/c.03:-45 to 160° F (70°C) • IRt/c, IRt/c.1X, IRt/c.3X, IRt/c.SV: -45 to 180°F (85C) • IRt/c, IRt/c.1X, IRt/c.3X up to 750°F (450°C) with CJK-1 air cooling jacket, up to 1000 °F (540 °C) with water cooling. • IRt/c.3X,: -45 to 240 °F (115 °C) with built in air purge, up to 750 °F (450 °C) with CJK-2 air cooling jacket • IRt/c.5, IRt/c.10, and all adjustable models: -45 to 400 °F (200 °C) with built in air purge www.exergen.com
CJK-2 Cooling Jacket www.exergen.com
SELECTING A PRE-CALIBRATED IRt/c ORDERING INFORMATION: (MODEL) - (THERMOCOUPLE TYPE) - (PRECALIBRATED TEMPERATURE RANGE) • Select IRt/c Model, based on field of view • Select thermocouple type desired • Select temperature range desired Example: IRt/c.3X-K-80F/27C www.exergen.com
Adjustable model IRt/c’s • Allow the user to calibrate to match a conventional t/c in whatever temperature range is desired • The ranges are -50 to 5000F and can cover limited linear ranges, see Tech Note 70 • Difficult optics can be obtained, such as slotted spot sizes and 100:1 FOV’s • Higher temperature ranges can be obtained • Wide linear ranges can be obtained with programmable input devices • HiE and LoE models available for high and low emissivity targets www.exergen.com
Ordering Adjustable Models • Select the model for temperature range, spot size, and target surface material. • MODEL - T/C TYPE - (HiE or LoE), example: IRt/c.10A - K - LoE • Adjustable model IRt/c’s are also available, precalibrated from Exergen with NIST traceability for quick multiple sensor installations www.exergen.com
IRt/c.20A www.exergen.com
WHAT INFORMATION IS NEEDED FROM ENDUSER TO SELECT IRt/c MODELS? • TARGET SIZE • DISTANCE BETWEEN SENSOR AND TARGET • SURFACE MATERIAL OF THE TARGET • THERMOCOUPLE OUTPUT DESIRED • TARGET’S TEMPERATURE RANGE • AMBIENT TEMPERATURE RANGE WHERE SENSOR IS MOUNTED • IS THERE DUST OR DIRT IN THE AIR? • WHAT IS THE INPUT DEVICE? www.exergen.com
Agriculture Asphalt Automotive Coatings Food Drying Electric Power Flame Detection Furnace Gas Glass Hazardous Materials Ice Laminating Machine tools Medical Equipment Metals TypicalIRt/c Applications • Oven Control • Packaging • Paint Curing • Plastics • Printing • Semiconductor • Soldering • Thermoforming • Webs www.exergen.com
Agriculture - Monitor plant temperature APOGEE INSTRUMENTS - UTAH www.exergen.com
Agriculture - Cotton canopy temperature for irrigation control USDA - Texas www.exergen.com