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35. CHECKS AND ADJUSTMENTS
272
4. Adjust the adjusting screws until
the tightening tension of the three
screws is the same to align the
bubble in the middle of the circle.
• Be careful that the tightening tension is identical for all the adjusting screws.
• Also, do not over-tighten the adjusting screws as this may damage the circular
level.
If the tilt angle shown on the display shifts from tilt angle 0° (zero point), the
instrument is not correctly levelled. This will adversely affect angle measurement.
Perform the following procedure to cancel the tilt zero point error.
PROCEDURE Check
1. Carefully level the instrument. If
necessary, repeat the procedures
to check and adjust the bubble
levels.
2. Set the horizontal angle to 0°.
Press
[0SET]
twice in the first
page of the OBS mode screen to
set the horizontal angle to 0°.
3. Select “Instr. const” in the Config.
mode screen to display the current
correction constant in the X
(sighting) direction and Y
(horizontal axis) direction.
35.2 Tilt Sensor
Instr.const
Tilt: X -10 Y 7
Colllimation
Config
Obs.condition
Instr.config
Comms setup
Unit
Instr.const