21 3
A. Introduction
B. WARNING & CAUTIONS
C. Distance to spot size
This infrared thermometer is used for measuring the tem-
perature of the object's surface, which is applicable for va-
rious hot, hazardous or hard-toreach objects without contact
safely and quickly.
This unit consist of Optics, Temperature Sensor Signal
amplifier, Processing circuit and LCD Display. The Optics
collected the infrared energy emitted by object and focus onto
the Sensor. Then the sensor translates the energy into an
electricity signal. This signal will be turned out to be digital
shown on the LCD after the signal amplifier and processing
circuit.
1. Warning:
To avoid the potential situation may cause harm or dam-
age to people, please pay attention to the following items:
1) . Do not point laser directly at eye or indirectly off reflec-
tive surfaces.
2) . The unit cannot measure through transparent surfaces
such as glass or plastic. It will measure the surface tem-
perature of these materials instead.
3) . Steam, dust, smoke, or other particles can prevent acc-
urate measurement by obstructing by the units optics.
2. Cautions:
Infrared thermometer should be protected for the
following:
1). EMF (electro-magnetic fields) from arc welders,
induction heaters.
2). Thermal shock (cause by large or abrupt ambient
temperature changes allow 30 minutes for unit to
stabilize before use).
3). Do not leave the unit on or near objects of high
temperature.
1. When take measurement, pay attention to the Distance
to Spot Size. As the Distance (D) from the target surface
increases, the spot size (S) of the area measured by the
unit becomes larger.
The Distance to Spot size of the unit is 12:1(Figure 1).
MODEL:WT320
Version：WT320-EN-0
Infrared Thermometer
Instruction Manual
D. EMISSIVITY
Emissivity: Most organic materials and painted or
oxidized surfaces have an emissivity of 0.95(preset in
the unit). Inaccurate readings will result from measuring
shiny or polished metal surfaces. To compensate for this,
adjust the units emissivity reading or cover the surface to
be measured with masking tape or flat black paint.
Measure the tape or painted surface when the tape or
painted reach the same temperature as the material
underneath.
2. Field of view:
Make sure the target is larger than the unit's spot size.
The smaller the target the closer measure distance.
When accuracy is critical, make sure the target is at least
twice as large as the spot size.
E. Operation
1. Operating the unit：Figure 2
1). Open the battery door and insert the battery.
2). Pull the trigger to turn on the unit;
3). Aim at the target surface and pull the trigger, then temp-
erature will be shown on the LCD.
This unit is equ ipped with a laser, which is only used for
aiming.
Trigger
Finger indents
Figure 2
25mm@
300mm
75mm@
900mm
125mm@
1500mm
1"@
12"
3"@
36"
5"@
60"
D:S=12:1
Figure 1
