Page 11
Wahl DHS520
6.0 OPTICS
User Manual
The
Wahl DHS520/520B
has a precision reflex optical system, which provides
user-focusable ‘through the lens’ sighting and gives precise definition of the
target spot. The specified focal range is 1m/39.4in to infinity.
6.1 Target Size Calculation
The precision reflex optical system gives a narrow field of view (180:1 to 98%
energy).
As the instrument is focusable, you can calculate an approximate target size
from the information given in Fig. 15.
target distance (D) from optical datum
field of view
optical
datum
target size (T)
Not to scale
target diameter (T) (mm) = target distance (D) from optical datum (mm) - 100
field of view (180)
or
target diameter (T) (in) = target distance (D) from optical datum (in) - 4
field of view (180)
315015
Fig. 15
Wahl DHS520/520B
thermometer target size calculation
Summary of Contents for Heat Spy DHS520
Page 2: ......
Page 3: ......
Page 9: ......
Page 12: ......
Page 14: ...Page 2 Wahl DHS520 User Manual Fig 1 Wahl DHS520 520B portable infrared thermometer ...
Page 21: ......
Page 35: ...User Manual Wahl DHS520 Page 22 Blank ...
Page 37: ......
Page 38: ...Wahl DHS520 Page 24 Blank UserGuide ...
Page 39: ...User Manual Wahl DHS520 ...
Page 40: ......
Page 45: ......
Page 51: ......
Page 59: ...Page 43 User Manual Wahl DHS520 ...