Spectra Precision Focus 8 Series, User Manual

Page: 47 / 70

Spectra Precision Focus 8 Series Total Station User Guide 4 5
Checking and Adjustment 4
a. Use the supplied hexagonal wrench to turn the adjustment screws until the
image of the X is in Position P. Position P is the center point of the line
connecting the X and the center of the reticle mark
.
b. Repeat from Step 2 .
For laser plummet adjustment, a cap needs to be removed.
Zero point errors of vertical scale and horizontal angle
corrections
Checking
1. Set up the instrument on the tripod.
2. Follow the leveling procedures described in Leveling, page 29 .
3. Flip the telescope to the Face-1 position.
4. Sight a target that is within 45° of the horizontal plane.
5. Read the vertical angle from the VA1 field in the Basic Measurement Screen
(BMS).
6. Rotate the instrument 180° and flip the telescope to the Face-2 position.
7. Read the vertical angle from the VA2 field.
8. Add the two vertical angles together, VA1 + VA2.
–
No adjustment is required if the zero reference for vertical angles (VA zero
setting) is set to Zenith, and VA1 + VA2 equals 360°.
–
No adjustment is required if the zero reference for vertical angles (VA zero
setting) is set to Horizon, and VA1 + VA2 is either 180° or 540°.
–
An adjustment is required if VA1 + VA2 is not one of the values listed above.
Note – The difference between the vertical angle reading the relevant angle (either 360° for
Zenith, or 180° or 540° for Horizon) is called the altitude constant .
Adjusting
There are two steps in the calibration program. Usually you only complete the first step
that is described below, because the trunnion axis is finely adjusted mechanically.