2-6

2 PREPARATION FOR MEASUREMENT
2.6 Vertical and Horizontal Angle Tilt Correction
When the tilt sensors are activated, automatic correction of vertical and horizontal angle for
mislevelment is displayed.
To ensure a precise angle measurement, tilt sensors must be turned on. The display can also be used
to fine level the instrument. If the (TILT OVER) display appears the instrument is out of automatic
compensation range and must be leveled manually.
lGTS-820A series compensates both the vertical an gle and the horizontal angle readings due to
inclination of the standing axis in the X and Y directions.
lFor more information about dual axis compensation, see Chapter “APPENDIX” “Dual Axis
Compensation”.
lThe display of Vertical or Horizont al angl e is unstable when instrument is on an unstable stage or a
windy day. You can tu rn off the auto tilt correction function of V/H angle in this case. To set TILT
correction mode ON/OFF, refer to next pag e or Ch apter 8 “PARAMETERS SETTING MODE”.
V
V
W
W
X
X
S
S
P
P
O
O
T
T
Q
Q
D
D
U
U
R
R
|
|
Standing axis
Zenith
Inclination of the standing
axis in the X direction
Standing axis
Zenith
Inclination of the standing
axis in the Y direction
Trunnion axis
Horizontal
When the instrument tilted over correction
range.
Rotate the leveling screws and level the
instrument.
After leveling (when each axis is within ±1'30"),
the display returns to the previous mode
automatically.
X,Y tilt correction range : within ±4'

X:

Y:

X:+0°00'00"
Y:+0°00'00"