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
μm). Although the wavelengths are given in μm (micrometers), other units are often
still used to measure wavelength in this spectral region, e.g. nanometer (nm) and
Ångström (Å).
The relationships between the different wavelength measurements is:
33.3 Blackbody radiation
A blackbody is defined as an object which absorbs all radiation that impinges on it
at any wavelength. The apparent misnomer black relating to an object emitting radia-
tion is explained by Kirchhoff’s Law (after Gustav Robert Kirchhoff, 1824–1887), which
states that a body capable of absorbing all radiation at any wavelength is equally
capable in the emission of radiation.
10398803;a1
Figure 33.2 Gustav Robert Kirchhoff (1824–1887)
The construction of a blackbody source is, in principle, very simple. The radiation
characteristics of an aperture in an isotherm cavity made of an opaque absorbing
material represents almost exactly the properties of a blackbody. A practical application
of the principle to the construction of a perfect absorber of radiation consists of a box
that is light tight except for an aperture in one of the sides. Any radiation which then
enters the hole is scattered and absorbed by repeated reflections so only an infinites-
imal fraction can possibly escape. The blackness which is obtained at the aperture
is nearly equal to a blackbody and almost perfect for all wavelengths.
By providing such an isothermal cavity with a suitable heater it becomes what is
termed a cavity radiator. An isothermal cavity heated to a uniform temperature gener-
ates blackbody radiation, the characteristics of which are determined solely by the
temperature of the cavity. Such cavity radiators are commonly used as sources of
radiation in temperature reference standards in the laboratory for calibrating thermo-
graphic instruments, such as a FLIR Systems camera for example.
170 Publ. No. T559597 Rev. a554 – ENGLISH (EN) – September 27, 2011
33 – Theory of thermography