GeoMax Zoom80 R, User Manual

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Technical Data Zoom80
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Atmospheric correction
°F Atmospheric corrections in ppm with temperature [°F], air pressure [inch Hg] and height [ft] at 60 % rela-
tive humidity.
7.1.9 Reduction Formulas
Measurements
Reflector types The reduction formulas are valid for measurements to all reflector types:
•
measurements to prisms, to reflector tape and reflectorless measurements.
Formulas The instrument calculates the slope distance, horizontal distance, height difference in accordance with the
following formulas:
Earth curvature (1/R) and mean refraction coefficient (k) (if enabled on the Refraction page in Main Menu:
Config...
\
Instrument Settings...
\
TPS Corrections) are automatically taken into account when calculating
the horizontal distance and height difference. The calculated horizontal distance relates to the station
height and not to the reflector height.
TS_109
130°F
120°F
110°F
100°F
90°F
80°F
70°F
60°F
50°F
40°F
30°F
20°F
10°F
0°F
-10°F
-20°F
130°F
120°F
110°F
100°F
90°F
80°F
70°F
60°F
50°F
40°F
30°F
20°F
10°F
0°F
-10°F
-20°F
16
[ ft ]
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 inch Hg
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 inch Hg
1600015000140001300012000 1100010000 9000 8000 7000 6000 5000 4000
3000 2000 1000
o ft
-15
-20
-25
-30
-35
-40
-45
-50
-55
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
11
0 11
5
120
125
130
135
140
145
a) Mean Sea Level
b) Instrument
c) Reflector
Slope distance
Horizontal distance
Height difference
c
a
b
TS_110
Displayed slope distance [m]
D
0
Uncorrected distance [m]
ppm Atmospheric scale correction [mm/km]
mm Additive constant of the reflector [mm]
Horizontal distance [m]
Height difference [m]
Y * |sin  |
X * cos 
 Vertical circle reading
A (1 - k/2)/R = 1.47 * 10
-7
[m
-1
]
B (1 - k)/2R = 6.83 * 10
-8
[m
-1
]
k 0.13 (mean refraction coefficient)
R 6.378 * 10
6
m (radius of the earth)
TS_111
= D0 · ( 1 + ppm · 10
-6
) + mm
TS_112
= Y - A · X · Y
TS_113
= X + B · Y
2