FLIR Systems FLIRT5590 User Manual
Application examples28
28.3 Oxidized socket
28.3.1 General
Depending on the type of socket and the environment in which the socket is installed, oxides may occur on the socket's contact surfaces. These oxides can lead to locally increased resistance when the socket is loaded, which can be seen in an infrared image
as local temperature increase.
A socket’s construction may differ dramatically from one manufacturer to another. For
this reason, different faults in a socket can lead to the same typical appearance in an infrared image.
Local temperature increase can also result from improper contact between a wire and
socket, or from difference in load.
28.3.2 Figure
The image below shows a series of fuses where one fuse has a raised temperature on
the contact surfaces against the fuse holder. Because of the fuse holder’s blank metal,
the temperature increase is not visible there, while it is visible on the fuse’s ceramic
material.
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28.4 Insulation deficiencies
28.4.1 General
Insulation deficiencies may result from insulation losing volume over the course of time
and thereby not entirely filling the cavity in a frame wall.
An infrared camera allows you to see these insulation deficiencies because they either
have a different heat conduction property than sections with correctly installed insulation,
and/or show the area where air is penetrating the frame of the building.
When you are inspecting a building, the temperature difference between the inside and
outside should be at least 10°C (18°F). Studs, water pipes, concrete columns, and similar components may resemble an insulation deficiency in an infrared image. Minor differences may also occur naturally.
28.4.2 Figure
In the image below, insulation in the roof framing is lacking. Due to the absence of insulation, air has forced its way into the roof structure, which thus takes on a different characteristic appearance in the infrared image.
28.5 Draft
28.5.1 General
Draft can be found under baseboards, around door and window casings, and above ceiling trim. This type of draft is often possible to see with an infrared camera, as a cooler
airstream cools down the surrounding surface.
When you are investigating draft in a house, there should be sub-atmospheric pressure
in the house. Close all doors, windows, and ventilation ducts, and allow the kitchen fan
to run for a while before you take the infrared images.
An infrared image of draft often shows a typical stream pattern. You can see this stream
pattern clearly in the picture below.
Also keep in mind that drafts can be concealed by heat from floor heating circuits.
28.5.2 Figure
The image below shows a ceiling hatch where faulty installation has resulted in a strong
draft.
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About FLIR Systems
FLIR Systems was established in 1978 to pioneer the development of high-performance
infrared imaging systems, and is the world leader in the design, manufacture, and marketing of thermal imaging systems for a wide variety of commercial, industrial, and government applications. Today, FLIR Systems embraces five major companies with
outstanding achievements in infrared technology since 1958—the Swedish AGEMA Infrared Systems (formerly AGA Infrared Systems), the three United States companies Indigo Systems, FSI, and Inframetrics, and the French company Cedip.
Since 2007, FLIR Systems has acquired several companies with world-leading expertise
in sensor technologies:
• Extech Instruments (2007)
• Ifara Tecnologías (2008)
• Salvador Imaging (2009)
• OmniTech Partners (2009)
• Directed Perception (2009)
• Raymarine (2010)
• ICx Technologies (2010)
• TackTick Marine Digital Instruments (2011)
• Aerius Photonics (2011)
• Lorex Technology (2012)
• Traficon (2012)
• MARSS (2013)
• DigitalOptics micro-optics business (2013)
• DVTEL (2015)
• Point Grey Research (2016)
• Prox Dynamics (2016)
Figure 29.1 Patent documents from the early 1960s
FLIR Systems has three manufacturing plants in the United States (Portland, OR, Boston,
MA, Santa Barbara, CA) and one in Sweden (Stockholm). Since 2007 there is also a
manufacturing plant in Tallinn, Estonia. Direct sales offices in Belgium, Brazil, China,
France, Germany, Great Britain, Hong Kong, Italy, Japan, Korea, Sweden, and the USA
—together with a worldwide network of agents and distributors—support our international customer base.
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About FLIR Systems
FLIR Systems is at the forefront of innovation in the infrared camera industry. We anticipate market demand by constantly improving our existing cameras and developing new
ones. The company has set milestones in product design and development such as the
introduction of the first battery-operated portable camera for industrial inspections, and
the first uncooled infrared camera, to mention just two innovations.
Figure 29.2 1969: Thermovision Model 661. The
camera weighed approximately 25 kg (55 lb.), the
oscilloscope 20 kg (44 lb.), and the tripod 15 kg
(33 lb.). The operator also needed a 220 VAC
generator set, and a 10 L (2.6 US gallon) jar with
liquid nitrogen. To the left of the oscilloscope the
Polaroid attachment (6 kg (13 lb.)) can be seen.
Figure 29.3 2015: FLIR One, an accessory to
iPhone and Android mobile phones. Weight: 90 g
(3.2 oz.).
FLIR Systems manufactures all vital mechanical and electronic components of the camera systems itself. From detector design and manufacturing, to lenses and system electronics, to final testing and calibration, all production steps are carried out and
supervised by our own engineers. The in-depth expertise of these infrared specialists ensures the accuracy and reliability of all vital components that are assembled into your infrared camera.
29.1 More than just an infrared camera
At FLIR Systems we recognize that our job is to go beyond just producing the best infrared camera systems. We are committed to enabling all users of our infrared camera systems to work more productively by providing them with the most powerful camera–
software combination. Especially tailored software for predictive maintenance, R & D,
and process monitoring is developed in-house. Most software is available in a wide variety of languages.
We support all our infrared cameras with a wide variety of accessories to adapt your
equipment to the most demanding infrared applications.
29.2 Sharing our knowledge
Although our cameras are designed to be very user-friendly, there is a lot more to thermography than just knowing how to handle a camera. Therefore, FLIR Systems has
founded the Infrared Training Center (ITC), a separate business unit, that provides certified training courses. Attending one of the ITC courses will give you a truly hands-on
learning experience.
The staff of the ITC are also there to provide you with any application support you may
need in putting infrared theory into practice.
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About FLIR Systems
29.3 Supporting our customers
FLIR Systems operates a worldwide service network to keep your camera running at all
times. If you discover a problem with your camera, local service centers have all the
equipment and expertise to solve it within the shortest possible time. Therefore, there is
no need to send your camera to the other side of the world or to talk to someone who
does not speak your language.
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Terms, laws, and definitions
Term Definition
Absorption and emission
Apparent temperature uncompensated reading from an infrared instrument, con-
Color palette assigns different colors to indicate specific levels of apparent
Conduction direct transfer of thermal energy from molecule to molecule,
Convection heat transfer mode where a fluid is brought into motion, ei-
Diagnostics examination of symptoms and syndromes to determine the
Direction of heat transfer
Emissivity ratio of the power radiated by real bodies to the power that is
Energy conservation
Exitant radiation radiation that leaves the surface of an object, regardless of
Heat thermal energy that is transferred between two objects (sys-
Heat transfer rate
Incident radiation radiation that strikes an object from its surroundings
IR thermography process of acquisition and analysis of thermal information
Isotherm replaces certain colors in the scale with a contrasting color. It
Qualitative thermography thermography that relies on the analysis of thermal patterns
Quantitative thermography thermography that uses temperature measurement to deter-
2
The capacity or ability of an object to absorb incident radiated energy is always the same as the capacity to emit its
own energy as radiation
taining all radiation incident on the instrument, regardless of
its sources
3
temperature. Palettes can provide high or low contrast, depending on the colors used in them
caused by collisions between the molecules
ther by gravity or another force, thereby transferring heat
from one place to another
nature of faults or failures
5
Heat will spontaneously flow from hotter to colder, thereby
transferring thermal energy from one place to another
radiated by a blackbody at the same temperature and at the
same wavelength
8
The sum of the total energy contents in a closed system is
4
6
7
constant
its original sources
tems) due to their difference in temperature
9
The heat transfer rate under steady state conditions is directly proportional to the thermal conductivity of the object,
the cross-sectional area of the object through which the heat
flows, and the temperature difference between the two ends
of the object. It is inversely proportional to the length, or
thickness, of the object
10
from non-contact thermal imaging devices
marks an interval of equal apparent temperature
to reveal the existence of and to locate the position of
anomalies
mine the seriousness of an anomaly, in order to establish repair priorities
12
12
11
2. Kirchhoff’s law of thermal radiation.
3. Based on ISO 18434-1:2008 (en).
4. Based on ISO 13372:2004 (en).
5. 2nd law of thermodynamics.
6. This is a consequence of the 2nd law of thermodynamics, the law itself is more complicated.
7. Based on ISO 16714-3:2016 (en).
8. 1st law of thermodynamics.
9. Fourier’s law.
10.This is the one-dimensional form of Fourier’s law, valid for steady-state conditions.
11.Based on ISO 18434-1:2008 (en)
12.Based on ISO 10878-2013 (en).
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Terms, laws, and definitions
Term Definition
Radiative heat transfer Heat transfer by the emission and absorption of thermal
Reflected apparent temperature apparent temperature of the environment that is reflected by
Spatial resolution ability of an IR camera to resolve small objects or details
Temperature measure of the average kinetic energy of the molecules and
Thermal energy total kinetic energy of the molecules that make up the
Thermal gradient gradual change in temperature over distance
Thermal tuning process of putting the colors of the image on the object of
radiation
the target into the IR camera
13
atoms that make up the substance
14
object
analysis, in order to maximize contrast
13
13.Based on ISO 16714-3:2016 (en).
14.Thermal energy is part of the internal energy of an object.
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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 temperature 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.
31.2.1 Finding the emissivity of a sample
31.2.1.1 Step 1: Determining reflected apparent temperature
Use one of the following two methods to determine reflected apparent temperature:
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31.2.1.1.1 Method 1: Direct method
Follow this procedure:
1. Look for possible reflection sources, considering that the incident angle = reflection
angle (a = b).
Figure 31.1 1 = Reflection source
2. If the reflection source is a spot source, modify the source by obstructing it using a
piece if cardboard.
Figure 31.2 1 = Reflection source
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3. Measure the radiation intensity (= apparent temperature) from the reflection source
using the following settings:
• Emissivity: 1.0
• D
: 0
obj
You can measure the radiation intensity using one of the following two methods:
Figure 31.3 1 = Reflection source Figure 31.4 1 = Reflection source
You can not use a thermocouple to measure reflected apparent temperature, because a
thermocouple measures temperature, but apparent temperatrure is radiation intensity.
31.2.1.1.2 Method 2: Reflector method
Follow this procedure:
1. Crumble up a large piece of aluminum foil.
2. Uncrumble the aluminum foil and attach it to a piece of cardboard of the same size.
3. Put the piece of cardboard in front of the object you want to measure. Make sure that
the side with aluminum foil points to the camera.
4. Set the emissivity to 1.0.
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5. Measure the apparent temperature of the aluminum foil and write it down. The foil is
considered a perfect reflector, so its apparent temperature equals the reflected apparent temperature from the surroundings.
Figure 31.5 Measuring the apparent temperature of the aluminum foil.
31.2.1.2 Step 2: Determining the emissivity
Follow this procedure:
1. Select a place to put the sample.
2. Determine and set reflected apparent temperature according to the previous
procedure.
3. Put a piece of electrical tape with known high emissivity on the sample.
4. Heat the sample at least 20 K above room temperature. Heating must be reasonably
even.
5. Focus and auto-adjust the camera, and freeze the image.
6. Adjust Level and Span for best image brightness and contrast.
7. Set emissivity to that of the tape (usually 0.97).
8. Measure the temperature of the tape using one of the following measurement
functions:
• Isotherm (helps you to determine both the temperature and how evenly you have
heated the sample)
• Spot (simpler)
• Box Avg (good for surfaces with varying emissivity).
9. Write down the temperature.
10. Move your measurement function to the sample surface.
11. Change the emissivity setting until you read the same temperature as your previous
measurement.
12. Write down the emissivity.
Note
• Avoid forced convection
• Look for a thermally stable surrounding that will not generate spot reflections
• Use high quality tape that you know is not transparent, and has a high emissivity you
are certain of
• This method assumes that the temperature of your tape and the sample surface are
the same. If they are not, your emissivity measurement will be wrong.
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31.3 Reflected apparent temperature
This parameter is used to compensate for the radiation reflected in the object. If the
emissivity is low and the object temperature relatively far from that of the reflected it will
be important to set and compensate for the reflected apparent temperature correctly.
31.4 Distance
The distance is the distance between the object and the front lens of the camera. This
parameter is used to compensate for the following two facts:
• That radiation from the target is absorbed by the atmosphere between the object and
the camera.
• That radiation from the atmosphere itself is detected by the camera.
31.5 Relative humidity
The camera can also compensate for the fact that the transmittance is also dependent
on the relative humidity of the atmosphere. To do this set the relative humidity to the correct value. For short distances and normal humidity the relative humidity can normally be
left at a default value of 50%.
31.6 Other parameters
In addition, some cameras and analysis programs from FLIR Systems allow you to compensate for the following parameters:
• Atmospheric temperature – i.e. the temperature of the atmosphere between the cam-
era and the target
• External optics temperature – i.e. the temperature of any external lenses or windows
used in front of the camera
• External optics transmittance – i.e. the transmission of any external lenses or windows
used in front of the camera
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