SETUP INSTRUCTIONS
INSTALL BATTERIES
The IRT850K is ready for use after you install two “AAA” batteries (not included) in the
instrument’s grip. To open the battery compartment (Fig. 1, Callout 7), pull the top of its hinged
cover away from the grip. Then install the two batteries in the compartment, using the + and –
marks inside it as a guide. Close the compartment by swinging the cover back to its original
position and snapping it shut.
OPERATING INSTRUCTIONS
BASIC OPERATION IN SCAN MODE
The IRT850K’s default operating mode is to scan a target object’s surface and display its
temperature.
To make a quick measurement
, point the infrared lens on the front of the instrument (Fig. 1,
Callout 8) at a target and squeeze and hold the measurement trigger (Callout 6). The temperature
of the target will instantly appear on the main (upper) readout in the thermometer’s default unit
of degrees Fahrenheit (°F). Before releasing the trigger, note the
SCAN
icon on the top line of
the display.
Now release the trigger and note that: 1) the main readout will hold the reading for 1 minute (as
indicated by the
HOLD
indication at the upper left of the LCD); and 2) the IRT will briefly display
the term
oFF
and then power off. This Auto Power Off (APO) function conserves battery life.
To make an accurate measurement
, use the IRT850K’s dual laser beams to define the
diameter of the target. Unlike convergent lasers used to identify the spot distance, the IR850K’s
dual lasers are designed to highlight the spot diameter beyond the focal point (see figure
below)—and therefore the target area—at any distance beyond the spot. This capability is not
just convenient, but also critical in making accurate temperature measurements.
Fig. 3. The IRT850K’s field of view, created by dual diverging laser beams
All IR thermometers, including the IRT850K, take the
average
temperature of all objects within a
circular target area. Depending on the distance to the target, the target area may include both the
target and background objects in the thermometer’s field of view. If background objects in the
field of view are cooler than the target, the measured temperature will be lower than the target’s
5
1 ft.
1.5 ft.
2 ft.
50 ft.
75 ft.
100 ft.
