Functional Principle - Forch 5439 35 2 Mode D'emploi

Functional principle

The non-contact temperature analyser measures the surface temperature of an object
by means of infrared radiation. In this case the totality of the detected infrared radiation
reflected from the optical measuring spot is focused onto the infrared sensor. The device
is able to calculate thereof the temperature value and displays it on the LCD screen. The
laser is only used for aiming.
Size of measuring spot
To obtain accurate results, the target must be larger than the spot size of the infrared
thermometer. The displayed temperature is the average temperature of the measured area.
The smaller the object, the shorter the distance to the infrared thermometer has to be. Please
determine the exact spot size by using the diagram below or check the values printed on the
device. For precise measurements the object should be at least twice as big as the spot size.
D (Distance) : S (Spotsize) = 10 : 1
Operation
For measuring temperatures you have to direct the opening of the IR-sensor (F) towards
the object to be measured, then press the push button for temperature measurement (H).
The LCD-display shows "SCAN" (2). Please make sure that the spot size is not bigger than
the object to be measured.
The found temperature value (11) is shown in the LCD-display. After having released the
push button for temperature measuring (H), the temperature value (11) is still displayed for
another 10 seconds. During this time "HOLD" (13) is displayed. After about 10 seconds the
device switches off automatically to save battery capacity.
By pressing the MODE-push button (B) you can switch between measurement functions
"MIN" (only displays the lowest temperature value during measurement) and "MAX" (only
displays the highest temperature value during measurement) or between the display of the
average temperatures. With the push button (E) you choose the measurement unit to be
displayed (°C / °F).
When the laser is activated it indicates the centre of the measuring spot which makes it easier
to do exact measurements. For activating the laser please press the push button "LASER
ON / OFF" (D) with the device being switched on. The LCD-display shows the laser icon (1).
If you press now the push button for temperature measurement (H), the laser incidates the
centre of the measuring spot. For deactivation press the push button "LASER ON / OFF" (D)
again, the laser icon (1) disappears. For measurements in the dark, you can activate and
deactivate the background light with the push button (C).