Omega Engineering OS533E manual Thermal Radiation, Appendix How Infrared Thermometry Works a

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Appendix: How Infrared Thermometry Works A

Thermal Radiation

Heat is transferred from all objects via radiation in the form of electromagnetic waves or by conduction or convection. All objects having a temperature greater than absolute zero

(-273°C, -459°F, 0 K) radiate energy. The thermal energy radiated by an object increases as the object gets hotter. Measurement of this thermal energy allows an infrared thermometer to calculate the object’s temperature if the emissivity (blackness) is known. Generally, it is convenient to measure the amount of radiated energy in the infrared part of an object’s radiation spectrum.

Figure A-1 shows a block diagram of an infrared radiation thermometer. Energy from the object is focused by the lens onto the detector. As the detector heats up, it sends out an electrical signal, which in turn is amplified and sent to the circuitry of the thermometer. The thermometer software then calculates the temperature of the object.

LENS

AMPLIFIER

DETECTOR

OBJECT

THERMOMETER CIRCUITRY AND DISPLAY

OR

SIGNAL OUTPUT TO SERIAL PRINTER

OR PERSONAL COMPUTER

Figure A-1. Infrared Thermometer Block Diagram

A-1

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Contents User’sGuide Servicing North America Unpacking Instructions Accessories Page Unpacking Instructions Chapter General Description Chapter Maintenance General Description Introduction OS530LE OS530HRE OS530LE-CF OS533E-CF OS534E-CF Features OS523E OS524E Parts of the Thermometer Front of the Thermometer LCDKey General Description General Description Ac Power Operation Installing the BatteriesOperating the Thermometer Field of View PositionsField of View OS534E, OS523E-1 Field of View OS53xE-CF Field of View OS523E-3 Measurement Techniques 11 Recorder Hookup Real Time Mode Active Operation 12. General Operational Block DiagramReal Time Modes 13. Visual Function Flow Chart Using the Trigger Function Adjusting EmissivityUsing the Lock Function Using the Distance Function Must be hard, flat, and reflective to ultrasonic pulseDS = 17. Field of View of Distance Meter HH-DM Calculating Temperature Values Laser Sighting StatusThermocouple Input OS532E, OS533E, OS534E Changing the Temperature from F to C or vice VersaTurning on the Display Backlighting Using the Alarm Functions To set the low alarm value OS533E, OS534E, OS523E, OS524E Use the Ambient Target Temperature Compensation Atcf PC User Application, OS530 Series Operation19. Main Menu Settings Menus 10. Settings Menu21. Typical Temperature Data File PC Interface Commands AsciiString Description Storing Temperature Data on Command OS534E, OS523E, OS524E Logging Temperature Data in Real Time OS523E, OS524E,OS534E Erasing the Temperature Data from Memory Recall Mode Passive Operation ModeRecall Modes Reviewing the Last Parameters Laser Sighting Description Right Side ViewTwo Laser Configurations Operating the Laser SightingLines of Sight of the Laser Sighting and Thermometer Installing and Operating the Sighting Scope Sighting ScopeInstalling the Sighting Scope Safety Warning Maintenance Replacing the BatteriesServicing the Laser Sighting Cleaning the LensCalibrating the Thermometer Troubleshooting Guide Problem SolutionTroubleshooting Guide Problem Troubleshooting Guide Specifications are for all models except where noted SpecificationsGND With Built-in Distance Module Laser Sighting Distance Measuring Built-in-DM Specifications Glossary of Key Strokes Glossary of Key Strokes Thermal Radiation Appendix How Infrared Thermometry Works aBlackbody Calculating Temperature Optics Field of View Metals Appendix Emissivity ValuesNonmetals Appendix Determining an Unknown Emissivity Figure C-1. Determining Emissivity Figure C-2. Determining Emissivity with a Drilled Hole Appendix Determining an Unknown Emissivity Index Field of View Diagrams Recall WARRANTY/DISCLAIMER Temperature PH/CONDUCTIVITY