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
28.3.3 Comparative measurement
For thermographic inspections of electrical installations a special method is used,
which is based on comparison of different objects, so-called measurement with a
reference. This simply means that you compare the three phases with each other.
This method needs systematic scanning of the three phases in parallel in order to
assess whether a point differs from the normal temperature pattern.
A normal temperature pattern means that current carrying components have a given
operation temperature shown in a certain color (or gray tone) on the display, which
is usually identical for all three phases under symmetrical load. Minor differences in
the color might occur in the current path, for example, at the junction of two different
materials, at increasing or decreasing conductor areas or on circuit breakers where
the current path is encapsulated.
The image below shows three fuses, the temperatures of which are very close to each
other. The inserted isotherm actually shows less than +2°C (+3.6°F) temperature
difference between the phases.
Different colors are usually the result if the phases are carrying an unsymmetrical
load. This difference in colors does not represent any overheating since this does not
occur locally but is spread along the whole phase.
10713203;a3
Figure 28.6 An isotherm in an infrared image of a fusebox
A ‘real’ hot spot, on the other hand, shows a rising temperature as you look closer
to the source of the heat. See the image below, where the profile (line) shows a
steadily increasing temperature up to about +93°C (+199°F) at the hot spot.
Publ. No. T559597 Rev. a554 – ENGLISH (EN) – September 27, 2011 135
28 – Introduction to thermographic inspections of electrical installations