Optex PT-7LD, Instruction Manual

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For the non-contact thermometer (infrared thermometer), the field of view (spot size) is specified
depending on the distance from the thermometer to the measuring object as shown below. The
temperature value displayed is the average temperature within the spot size. To take an accurate
measurement, check the correlation between the size of object and the distance to it.
[Field of View]
* Remarks
ex.) The average temperature of surface of the circle 25 mm in diameter is measured at a distance of 300 mm
away from the measuring object.
* The laser beam points 13mm off to the left from the center of the field of view. The laser marker functions as a
sighting method and not a sensing element.
* It is possible to take temperatures with this thermometer at a distance of 1,000 mm or more away from the
measuring object, unless there is any obstacle. However, please note that the measuring field of view enlarges
in proportion to the measuring distance. This thermometer has an optical resolution of 15:1 [D(Distance to the
measuring object):S(Spot size)].
[For Correct Measurement]
The optical resolution values stated in "Field of View" are at minimum 90% energy. The size of measuring object
should be sufficiently larger than the field of view (spot size) shown in the above illustration.
Note. If any water drop is on the filter and/or the area around it, the thermometer measures temperature
of the water drop, which results in incorrect measurement. Wipe up the filter and the area around
it completely before taking measurement. (See "Maintenance" on page 16)
Field of View
9
INCORRECT
CORRECT
The measuring object is bigger
than the field of view.
The measuring object is smaller
than the field of view.
The temperature of background
influences on the measuring value.