Unit UT305A User manual

Title Page
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Table of Contents
Introduction
Contacting Uni-Trend
Safety Information
Features
Display
Buttons and Connector
How the Thermometer works.
Operating the Thermometer
Locating a Hot or Cold Spot
Distance and Spot Size
Field of View
Emissivity
User Setup
Emissivity Setup
Trigger Lock Setup
Switching
HAL Setup
LAL Setup
DATA
TC-K Thermocouple Measurement
HOLD
Typical Measurements
Testing Contactors (Starters)
Testing Enclosed Relays
Testing Fuses and Buss Connections
Testing Electrical Connections

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Title Page
Table of Contents
Scanning Walls for Air Leaks or Insulation Deficiencies
Testing Bearings
Testing Belts and Sheaves
Checking Hydronic Radiant Heat Applications
Measuring Grille, Register, or Diffuser Discharge Temperature
Checking for Blockage in Air-To-Air Evaporators or Condensers
Maintenance
Changing the Battery
Cleaning the Lens
Cleaning the Housing
Troubleshooting
CE Certification
Specifications
Infrared and T-C Thermocouple
Laser
Electrical
Physical
Environmental

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Table Title Page
List of Tables
1. Symbols
2. Buttons and Connector
3. Surface Emissivity
4. Troubleshooting

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Figure Title Page
List of Figures
1 Symbols and Safety Markings
2 Infrared Thermometer
3 Thermometer Display
4 Buttons and Connector
5 Locating Hot or Cold Spot
6 Distance and Spot Size
7 Field of View

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Introduction
The Model UT305A/B/C and UT306A/B/C Infrared
Thermometer (hereafter, the “Thermometer”) can
determine the surface temperature by measuring the
amount of infrared energy radiated by the target’s
surface. They have different distance to spot (D:S)
figure and different temperature range, details see the
contents.
The Thermometers are non-contact infrared thermometer
with low consumption design so that they can be used
for a longer time, which can solve the frequently changing
battery and low battery issues during measurement.
Intelligent design can make measurement easier and
quicker. The Thermometer can intelligently select battery
or USB power source.
This Manual uses UT305A as illustration.
Contacting Uni-Trend
To contact Uni-Trend. call (852) 2950 9168 or visit Uni-
Trend web site at
Safety Information
Warning
A warning identifies conditions and actions that
pose hazards to the user. To avoid electrical shock
or personal injury, follow these guidelines:
l Do not point laser directly at eye or indirectly
off reflective surfaces.
l Before using the Thermometer inspect the
case. Do not use the Thermometer if it appears
damaged. Look for cracks or missing plastic.
l Replace the battery as soon as the battery
indicator appears.
l Do not use the Thermometer if it operates
abnormally. Protection may be impaired. When
in doubt, have the Thermometer serviced.
l Do not operate the Thermometer around
explosive gas, vapor, or dust.
l To avoid a burn hazard, remember that highly
reflective objects will often result in lower than
actual temperature measurements.
l Do not use in a manner not specified by this
manual or the protection supplied by the
equipment may be impaired.

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Caution
To avoid damaging the thermometer or the
equipment under test protect them from the
following:
l EMF (electro-magnetic fields) from arc welders,
induction heaters, etc.
l Static electricity.
l Thermal shock (caused by large or abrupt
ambient temperature changes – all 30 minutes
from the Thermometer to stabilize before
use).
l Do not leave the Thermometer on or near
objects of high temperature.
Table 1 and Figure 1 show various symbols and safety
markings that are on the Thermometer and in this
manual.
Table 1. Symbols
Symbol Explanation
Risk of danger. Important information.
See Manual.
Warning. Laser
Conforms to Standards of European
Union
Battery

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Features
The Thermometer includes:
l Single-spot Laser Sighting
l Intelligent USB power source
l Two level white colour Backlit Display (when using
USB power up, this feature will be on automatically).
l Current Temperature Plus MIN, MAX, DIF, AVG
Temperature Displays/
l Easy Emissivity Selector
l Trigger Locked
l Degree Celsius and Fahrenheit Temperature
Selectable
l Tripod mount
l One 9V Battery

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Display
The primary temperature display reports the current or
last IR temperature read until the 8-second hold time
elapses.
The secondary temperature display reports a choice of
maximum, minimum, difference between maximum and
minimum temperature or average value.
You can toggle through the maximum, minimum,
difference and average IR temperatures anytime the
display is on by pressing the yellow button. The MAX,
MIN, DIF andAV temperatures are constantly calculated
and updated when the trigger is pressed. After the
trigger is released, the MAX, MIN, DIF and AV
temperatures are held until the Thermometer is auto
power off.
Notes
When the battery is low , appears on the display.
The last selection (MAX/MIN/DIF/AVG) is maintained
on the secondary display even after the Thermometer
has been turned off, providing the batteries have not
failed.

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Buttons and Connector
Figure 4. Buttons and Connector

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How the Thermometer Works
Infrared thermometers measure the surface temperature
of an opaque object. The Thermometer’s optics sense
infrared energy, which is collected and focused onto a
detector. The Thermometer’s electronics then translate
the information into a displayed temperature reading
which appears on the display. The laser is used for
aiming purposes only.
Operating the Thermometer
The Thermometer turns on when you press the trigger.
The Thermometer turns off when no activity is detected
for 8 seconds.
To measure temperature, aim the Thermometer at the
target, pull and hold the trigger. Release the trigger to
hold a temperature reading.
Be sure to consider distance-to-spot size ratio and filed
of view. The laser is used for aiming only.
Locating a Hot or Cold Spot
To find a hot or cold spot, aim the Thermometer outside
the target area. Then, slowly scan across the area with
an up and down motion until you located the hot or cold
spot. See Figure 5.
Figure 5. Locating Hot or Cold Spot

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Distance and Spot Size
As the distance (D) from the target being measured
increases, the spot size (S) of the area measured by
the unit becomes larger. The spot size indicates 90%
encircled energy. The maximum D:S is obtained when
the Thermometer is 600mm (60 in) form the target
resulting in a spot size of 20mm (2 in). See Figure 6.
Figure 6. Distance and Spot Size
Field of View
Make sure that the target is larger than the spot size.
The smaller the target, the closer you should be to it.
See Figure 7.
Figure 7. Field of View

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Emissivity
Emissivity describes the energy-emitting characteristics
of materials. Most organic materials and painted or
oxidized surfaces have an emissivity of about 0.95.
If possible, to compensate for inaccurate readings that
may result from measuring shiny metal surfaces, cover
the surface to be measured with masking tape or flat
black paint (<150 / 302 ) and use the high emissivity
setting. Allow time for the tape or paint to reach the
same temperatures as the surface beneath it. Measure
the temperature of the tape or painted surface.
If you cannot use paint or use tape, then you could
improve the accuracy of your measurements with the
emissivity selector. Even with emissivity selector, it can
be difficult to get a completely accurate infrared
measurement of a target with a shiny or metallic surface.
User Setup
Press SET button to step through Emissivity Setup
Trigger Lock Switching / Normal Measurement.
Press YELLOW button to save and exit Setup.
Emissivity Setup
This feature is to change the value of emissivity.
To adjust values for emissivity, follow the below
procedure:
1. Press SET to select emissivity set up, icon E=0 on
the display is blinking.
2. Press to increase the value by 0.01 or press and
hold to access quick setting. The maximum value
is 1.00.
3. Press to decrease the value by 0.01 or press and
hold to access quick setting. The minimum value
is 0.10.

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The Thermometer allows you to adjust the unit’s
emissivity for the type of surface before measured.
Refer to Table 2. But it is only a typical case. You could
base on your own case and materials to have different
setting.

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Trigger Lock Setup.
This feature is to set trigger lock or unlock
To lock or unlock the trigger, follow the below procedures:
1. Press SET to select trigger lock setting, the is blinking.
2. Press or to select ON or OFF.
When the trigger is locked, the Thermometer is on for
continues measurement, there is no need to pull the
trigger.
When the trigger is unlocked, user needs to pull the
trigger for measurement. When you release the trigger,
the Thermometer will keep hold the measurement result
automatically.
Switching /
This feature is to select or .
1. Press SET to choose / selection mode,
2. Press or to select or .
HAL Setup
This feature is to set up the high limit. When carrying
out measuring, the Thermometer beeps continuous if
the temperature is over this limit.
1. Press YELLOW button to toggle to HAL mode.
2. Press to increase the value by 0.1 or press and
hold to access quick setting until the maximum
value is reached. The thermometer stops and beeps.
3. Press to decrease the value by 0.1 or press and
hold to access quick setting until the minimum
value is reached or it lower than LAL value. The
thermometer stops and beeps.
4.Press SET to confirm this setting, the LCD displays
5. This feature is not valid when carrying out
measurement with TC-K type thermocouple
6. HAL value cannot set below the LAL value.

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LAL Setup
This feature is to set up the low limit. When carrying
out measuring, the Thermometer beeps continuous if
the temperature is below this limit.
1. Press YELLOW button to toggle to LAL mode.
2. Press to increase the value by 0.1 or press and
hold to access quick setting until the maximum
value is reached or higher than HAL value. The
thermometer stops and beeps.
3. Press to decrease the value by 0.1 or press and
hold to access quick setting until the minimum
value is reached. The thermometer stops and beeps.
4. Press SET to confirm this setting, the LCD displays
5. This feature is not valid when carrying out
measurement with TC-K type thermocouple
6. HAL value cannot set higher than the LAL value.
DATA
This feature is to store the data measuring under infrared
mode.
1. The maximum number of data to be stored is 99.
2. When the storage is empty, it displays “--- . ---“
3. Under non-measurement mode, press and hold DATA
and for 8 seconds to clear the stored data, the
Thermometer beeps.
4. Under measurement mode, press YELLOW button
to toggle to DATA mode.
5. Press or to select the location of storing the data.
6. Press DATA to store the value.
TC-K Thermocouple Measurement
This feature is to measure temperature with K type
thermocouple.
1. Press YELLOW button to toggle to T-C mode. The
LCD display shows OL before the thermocouple is
connected.
2. Connect the K type thermocouple, press the trigger
to start measuring. The LCD display shows the
reading.
3. Release the trigger, the reading is kept, LCD shows
T-C. The temperature reading is shown on the bottom
of right hand side.

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HOLD
The display will remain activated 8 seconds after the
trigger is released. HOLD appears in the upper middle
of the display. When the trigger is pulled again, the
Thermometer will begin measuring in the last function
selected.
Typical Measurements
This section describes a variety of measurements often
performed by technicians.
Reminder:
l User could select to turn on or off the backlight
and laser whenever you are making readings with
the Thermometer. But if you are using USB to
power up the Thermometer, the two levels white
colour backlight will be on automatically.
l Relatively high emissivity normally means emissivity
setting of about 0.95.
l Relatively low emissivity normally means emissivity
setting of about 0.30.
l When user cannot identify the emissivity of the
object to be measured, user could cover the surface
to be measured (temperature >150 ) with black
electric tape (emissivity of about 0.95). Allow time
for the tape to reach the same temperature as the
object to be measured. Measure and record the
temperature of the tape.
Target theThermometer to the object to be measured,
adjust the emissivity setting to make it as the same
temperature as the tape.At this time, theThermometer
emissivity setting is close to the emissivity of the
object to be measured, measurement could be started.
Testing Contactors (Starters)
1. Press SET to select emissivity. Press /to select
relatively low emissivity for bright contacts, or 0.7 mid
level for darkened contacts.
2. Press YELLOW button to select MAX.
3. Measure line and load side of one pole without
releasing trigger
4. A temperature difference between the line and load
sides of a pole indicate increased resistance of one
point and a contactor may be failing.

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Testing Enclosed Relays
1. Press SET and then press /to set emissivity to
relatively low for uninsulated connectors or relatively
high for plastic encased relays or for bakelite enclosed
relays or insulated connectors.
2. Press YELLOW button to select MAX.
3. Start to scan.
4. Measure the relay casing, looking for hot spots.
5. Measure electrical connections on relay terminals
looking for hot spots.
Testing Fuses and Buss Connections
1. Press SET and then press /to set emissivity to
relatively high for paper covered fuse body or insulated
connections.
2. Press YELLOW button to select MAX.
3. Scan the paper covered length of fuse.
4. Without releasing the trigger, scan each fuse. Unequal
temperatures between fuses may indicate voltage
or amperage imbalance.
5. Press SET and then press /to set emissivity to
relatively low, for metal fuses and caps and insulated
buss connections.
6. Press YELLOW button to select MAX.
7. Scan each end cap on each fuse/
Note
Unequal temperatures or a high temperature indicates
loose or corroded connection through the fuse buss
spring clip.
Testing Electrical Connections
1. Press SET and then press /to set emissivity to
relatively low for uninsulated connectors or buss
connections or relatively high for insulated connections.
Note
Conductors are typically smaller than the Thermometer’s
spot size. If the spot size is bigger than the connector,
the temperature reading is the average within the spot.
2. Scan the conductor, moving toward direction of
electrical connector (quick connect, wire nut, buss
connection, or lug).

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Scanning Walls for Air Leaks or Insulation
Deficiencies
1. Turn off heating, cooling, and blower.
2. Press SET to select emissivity. Press / to select
emissivity relatively high for painted surfaces or
window surfaces.
3. Press YELLOW button to select MIN when opposite
side of wall is at lower temperature and or select MAX
when opposite side of wall is at higher temperature.
4. Measure an interior partition wall surface temperature.
Do not release the trigger. Record this temperature
as your baseline (or benchmark) for a “perfectly”
insulated wall.
5. Face the wall to be scanned. Stand 1.2m away to
scan a 10cm spot on the wall.
6. Scan horizontal rows of wall from top to bottom, or
horizontal rows of ceiling from wall to wall. Look for
greatest deviations from baseline temperature to
identify problems. This completes the insulation test
scan.
Turn on the blower (no heat, no cooling) and retest. If
test results with the blower on are different than results
with the blower off, this may indicate air leaks in
conditioned envelope walls. The air leaks are caused
by duct leaks that create a pressure differential across
the conditioned space envelope.
Testing Bearings
Warning
To avoid injury when testing bearings:
l Do not wear loose clothing, jewelry, or anything
around neck when working around moving parts
such as motors, belts, blower, and fans.
l Make sure an electrical disconnect is within
reach and operating correctly and freely.
l Do not work alone.

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Note
It works best to compare two similar motors operating
similar loads.
1. Press SET and then press /to select relatively
high emissivity.
2. Press YELLOW button to select MAX.
3. Enable motor and allow it to reach steady state
operating temperatures.
4. Disable the motor if possible.
5. Measure the two motor bearing temperatures
6. Compare the two motor bearing temperatures.
Unequal temperatures or a high temperature can
indicate a lubrication or other bearing problem that
is resulting from excess friction.
7. Repeat the sequence for the blower bearings.
Testing Belts and Sheaves
1. Press SET and then press /to select relatively
high emissivity.
2. Press YELLOW button to select MAX.
3. Enable the motor and allow it to reach a steady state
operating temperatures.
4. Aim theThermometer at the surface to be measured.
5. Start recording temperature
6. Slowly move the Thermometer up the belt toward
second sheave.
l If belt is slipping, sheave temperature will be high
from friction.
l If belt is slipping, belt temperature will remain
high between sheaves.
l If belt is not slipping, belt temperature will reduce
between sheaves.
l If inner surfaces of sheaves are not a true “V”
shape, this indicates belt slippage and will continue
to operate at elevated temperatures until sheave
is replaced.
l Sheaves must be properly aligned (include “pitch
& yaw”) for belt and sheaves to operate at appropriate
temperatures. A straight edge or taut string, can
be used to check alignments.
l Motor sheave should operate at a temperature
consistent with blower sheaves.
l If motor sheave is at a higher temperature at motor
shaft than at outer circumference, belt is probably
not slipping.