B) Ir Measuring Optics - Ratio Measuring Distance:measuring Surface; C) Target Laser - VOLTCRAFT IR 1201-50D Operating Instructions Manual

b) IR measuring optics - ratio measuring distance:measuring surface

(D:S = Distance:Spot)
In order to obtain precise measuring results, the measured object must be larger than the IR measuring spot. The
measured temperature is calculated using the average temperature of the measured area. The smaller the object,
the closer it must be to the thermometer. The exact size of the measuring spot is shown in the following diagram. It is
also indicated on the thermometer. To ensure precise measurements, the measured object should be at least twice
the size of the IR measuring spot.
The smallest measurement diameter is achieved up to a distance of 90 cm. The measurement diameter is 18 mm.
However, keep sufficient distance to avoid faulty measurement due to heating of the IR thermometer.
Example: At a distance of 2 m, the measurement diameter is 40 mm.

c) Target laser

The target laser is active depending on the default setting during measurement. A warning symbol appears in the
display if the laser is active (E). Never look into the laser outlet (8) during a reading.
The target laser is constructed in dual design and marks the inner, approximate edge area of the measuring surface
(approx. 90%).
When both laser spots meet, the smallest measuring surface has been achieved. This is 18 mm in diameter.
With larger distances, the two laser spots move apart, analogue to the measuring surface.
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