User's Manual
Table Of Contents
- Table of contents
- 1 Warnings & Cautions
- 2 Notice to user
- 3 Customer help
- 4 Documentation updates
- 5 Important note about this manual
- 6 Parts lists
- 7 Quick Start Guide
- 8 Camera parts
- 9 Screen elements
- 10 Navigating the menu system
- 11 Connecting external devices and storage media
- 12 Pairing Bluetooth devices
- 13 Configuring Wi-Fi
- 14 Handling the camera
- 15 Working with images
- 16 Working with thermal fusion and picture-in-picture image modes
- 17 Working with measurement tools
- 18 Fetching data from external Extech meters
- 19 Working with isotherms
- 20 Annotating images
- 21 Recording video clips
- 22 Changing settings
- 23 Cleaning the camera
- 24 Technical data
- 25 Dimensional drawings
- 25.1 Camera dimensions, front view (1)
- 25.2 Camera dimensions, front view (2)
- 25.3 Camera dimensions, side view (1)
- 25.4 Camera dimensions, side view (2)
- 25.5 Camera dimensions, side view (3)
- 25.6 Infrared lens (30 mm/15°)
- 25.7 Infrared lens (10 mm/45°)
- 25.8 Battery (1)
- 25.9 Battery (2)
- 25.10 Battery (3)
- 25.11 Battery charger (1)
- 25.12 Battery charger (2)
- 25.13 Battery charger (3)
- 25.14 Battery charger (4)
- 26 Application examples
- 27 Introduction to building thermography
- 27.1 Disclaimer
- 27.2 Important note
- 27.3 Typical field investigations
- 27.3.1 Guidelines
- 27.3.2 About moisture detection
- 27.3.3 Moisture detection (1): Low-slope commercial roofs
- 27.3.4 Moisture detection (2): Commercial & residential façades
- 27.3.5 Moisture detection (3): Decks & balconies
- 27.3.6 Moisture detection (4): Plumbing breaks & leaks
- 27.3.7 Air infiltration
- 27.3.8 Insulation deficiencies
- 27.4 Theory of building science
- 27.4.1 General information
- 27.4.2 The effects of testing and checking
- 27.4.3 Sources of disruption in thermography
- 27.4.4 Surface temperature and air leaks
- 27.4.5 Measuring conditions & measuring season
- 27.4.6 Interpretation of infrared images
- 27.4.7 Humidity & dew point
- 27.4.8 Excerpt from Technical Note ‘Assessing thermal bridging and insulation continuity’ (UK example)
- 28 Introduction to thermographic inspections of electrical installations
- 28.1 Important note
- 28.2 General information
- 28.3 Measurement technique for thermographic inspection of electrical installations
- 28.4 Reporting
- 28.5 Different types of hot spots in electrical installations
- 28.6 Disturbance factors at thermographic inspection of electrical installations
- 28.7 Practical advice for the thermographer
- 29 About FLIR Systems
- 30 Glossary
- 31 Thermographic measurement techniques
- 32 History of infrared technology
- 33 Theory of thermography
- 34 The measurement formula
- 35 Emissivity tables
31 Thermographic measurement
techniques
31.1 Introduction
An infrared camera measures and images the emitted infrared radiation from an object.
The fact that radiation is a function of object surface temperature makes it possible
for the camera to calculate and display this temperature.
However, the radiation measured by the camera does not only depend on the tem-
perature of the object but is also a function of the emissivity. Radiation also originates
from the surroundings and is reflected in the object. The radiation from the object
and the reflected radiation will also be influenced by the absorption of the atmosphere.
To measure temperature accurately, it is therefore necessary to compensate for the
effects of a number of different radiation sources. This is done on-line automatically
by the camera. The following object parameters must, however, be supplied for the
camera:
■ The emissivity of the object
■ The reflected apparent temperature
■ The distance between the object and the camera
■ The relative humidity
■ Temperature of the atmosphere
31.2 Emissivity
The most important object parameter to set correctly is the emissivity which, in short,
is a measure of how much radiation is emitted from the object, compared to that from
a perfect blackbody of the same temperature.
Normally, object materials and surface treatments exhibit emissivity ranging from
approximately 0.1 to 0.95. A highly polished (mirror) surface falls below 0.1, while an
oxidized or painted surface has a higher emissivity. Oil-based paint, regardless of
color in the visible spectrum, has an emissivity over 0.9 in the infrared. Human skin
exhibits an emissivity 0.97 to 0.98.
Non-oxidized metals represent an extreme case of perfect opacity and high reflexivity,
which does not vary greatly with wavelength. Consequently, the emissivity of metals
is low – only increasing with temperature. For non-metals, emissivity tends to be high,
and decreases with temperature.
160 Publ. No. T559597 Rev. a554 – ENGLISH (EN) – September 27, 2011