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
28.6 Disturbance factors at thermographic inspection of
electrical installations
During thermographic inspections of different types of electrical installations, distur-
bance factors such as wind, distance to object, rain or snow often influence the
measurement result.
28.6.1 Wind
During outdoor inspection, the cooling effect of the wind should be taken into account.
An overheating measured at a wind velocity of 5 m/s (10 knots) will be approximately
twice as high at 1 m/s (2 knots). An excess temperature measured at 8 m/s (16 knots)
will be 2.5 times as high at 1 m/s (2 knots). This correction factor, which is based on
empirical measurements, is usually applicable up to 8 m/s (16 knots).
There are, however, cases when you have to inspect even if the wind is stronger than
8 m/s (16 knots). There are many windy places in the world, islands, mountains, and
so on but it is important to know that overheated components found would have
shown a considerably higher temperature at a lower wind speed. The empirical cor-
rection factor can be listed.
Correction factorWind speed (knots)Wind speed (m/s)
121
1.3642
1.6463
1.8684
2.06105
2.23126
2.40147
2.54168
The measured overheating multiplied by the correction factor gives the excess tem-
perature with no wind, that is, at 1 m/s (2 knots).
28.6.2 Rain and snow
Rain and snow also have a cooling effect on electrical equipment. Thermographic
measurement can still be conducted with satisfactory results during light snowfall
with dry snow and light drizzle, respectively. The image quality will deteriorate in heavy
146 Publ. No. T559597 Rev. a554 – ENGLISH (EN) – September 27, 2011
28 – Introduction to thermographic inspections of electrical installations