Technical Data
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Formulas
The instrument calculates the slope distance, horizontal distance, height differ-
ence 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 Correc-
tions) 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.
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
