Chauvin Arnoux C.A 871 Notice De Fonctionnement page 11

4. Point the thermometer at the target whose temperature you
wish to measure, with or without using the LASER
viewfinder.
5. Press the trigger to measure the temperature (if you hold
the trigger in this position, the thermometer will continuously
measure variations in temperature)
6. Release the trigger. The displayed value is the last value
measured.
NB: The instrument automatically shuts down after a few
seconds, storing the last configuration in its memory.
4.2 Precautions for use
■ If the surface to be measured is ≤ ÿ 50mm, hold the probe
as close as possible to the surface (less than 40cm away)
■ If the surface to be measured is covered in frost or other
particles, clean it so that it is properly exposed, before
taking a measurement.
■ If the surface to be measured is highly reflective, apply matt
tape or paint to the surface before measuring.
■ If the thermometer appears to be giving incorrect indications,
check the condition of the lens at the measurement opening,
as it may be obscured by condensation or particles. If so,
clean it by carefully following the instructions in § 6.3 Taking
Care of Your CA 871 Infrared Thermometer.
4.3 Ratio between distance from target/diameter
of measurement field
This ratio, also called the field of vision, indicates the diameter
of the measurement field at a given distance from the target;
D/Ø = 8/1 (see figure below).
The minimum measurement distance is 112mm; at this
distance, the diameter of the measurement field is
14mm.
When measuring smaller areas, it is important to bring the
probe sufficiently close to the target to avoid including other
points in the measurement field.
Refer to the diagram on the instrument's side panel!
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