Application Note

Application Note
From the Fluke Digital Library @ www.fluke.com/library
Infrared thermometers:
electrical, industrial, and
HVAC applications
In general, there are three ways to use any
kind of infrared, non-contact thermometer:
• Measuring the temperature at a spot
 Thistypeofmeasurementisusedtomeasureandtrack
temperatureatasinglespot.Itisusefulfortrendingthe
temperatureofanobjectorcomparingameasurementto
aspecification.Athermometerwithhighrepeatabilityhelps
ensureconsistencyforthiskindofmeasurement.
• Comparing the temperature of two spots
 Thistypeofmeasurementmightbeusedtocheckthefunc-
tioningofasteamtrapbymeasuringthetemperatureofthe
inletandoutlet.Nochangeindicatesthetraphasfailedopen.
Averylargechangeindicatesthetraphasfailedclosed.
• Scanning an object and detecting changes within a
continuous area on it
 Thiscapabilityallowstheusertofindhotorcoldspotson
housings,panels,andstructures.Forexample,onecan
checktheheatsinkofair-cooledtransformersforcooltubes
thatindicatearestrictedfloworalackofflow.
Applications for infrared
thermometers
Infrared thermometry can be
used for process monitoring,
plant predictive and preventive
maintenance, electrical applica-
tions, quality assurance, and
other applications.
IR non-contact thermometers
are ideal for moving targets
and machinery, hazardous and
inaccessible or distant targets,
electrical components, “big pic-
ture” evaluations of machinery
or surfaces, trending records,
and even protection against
litigation and insurance claims.
In fact, insurance companies are
encouraging their customers to
implement preventive infrared
scanning.
IR thermometers and imagers
can save time and money for
contractor and customer alike,
as well as perform diagnostics
that were previously impossible
without shutting down systems.
Here are some suggestions
for applications in which IR
non-contact thermometers have
proven useful:
Electrical maintenance
Check for heat buildup created
by loose connectors. Trouble-
shoot problems in battery banks
and power panel terminations,
ballasts, switchgear and fuse
connections. Identify hot spots
in the output filters on DC bat-
tery connections.
They can be used to inspect
supply power connections and
circuit breakers (or fuses) for
equal temperatures. They are
effective in determining the
source of the problem when
a thermal overload protection
device does not work and the
motor shuts down.