4.1 Precautions for use
If the surface to be measured is ≤ Ø 1.96" (50mm), hold the probe as close as
possible to the surface (less than 15" [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 indi-
cations, 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 § 5.
4.2 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/S = 12:1 (D = distance, S = spot).
•
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 as shown below.
8
CHAPTER 4
OPERATION
3.0@36
1.0@12
25@300
75@900
5.0@60 inch
125@1500 mm
Infrared Thermometer Model CA879