When to Use Infrared Temperature Measurement
Surface Is:
- Too Hot to Be Measured With Thermocouples
- Too Large to Be Measured Without a Very Large Number of Thermocouples
- Moving Too Much for Thermocouple Lead Wire to Accept Without Breaking
- At So High an Electrical Potential That Use of a Thermocouple Would Be Dangerous
- Low in Mass That The Thermocouple Itself Will Affect the Unknown Surface Temperature
- Too Fragile or Wet to Accommodate Thermocouple Contact
- Too Active (Chemically) to Accept a Thermocouple or Its Probe
- In an Atmosphere That Is Hostile to a Thermocouple
- Inaccessible to a Thermocouple or Its Instrumentation
- Near Noise Producing Electric or Magnetic Fields
Key Infrared Application Factors
- Target Spot Size and Distance
- Target Material (for Emissivity)
- Fixed or Handheld Unit
- Temperature Range
- Response Time
- Sighting System
- Environment
- Viewing Port
- Options Needed
Determination of Infrared Emissivity
- Measure Surface Temperature by Some Other Means (After Stopping Motion)
- Place Masking Tape on Surface (Emissivity 0.95)
- Drill Hole in Surface At Least Six Times as Deep as It Is Wide (Emissivity 0.95)
- Paint Surface Dull Black (M IR Region)
- Look up Emissivity in Table (Last Resort)
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