User's Manual

4 Checking and Adjustment
36 Total Station Nivo Series Instruction Manual
Trunnion axis compensation
The trunnion axis error is reported when the vertical axis and the trunnion axis
(horizontal axis) are not perpendicular to each other. The sighting axis error is from
the sighting and the trunnion axes. These two errors can be compensated by applying
the Tr-axis and ACH parameters on this instrument to horizontal angle readings.
Because the amount of compensation changes according to the vertical angle, when
compensation is enabled there is a slight movement in horizontal angle even if you
clamp the tangent screw.
Tr-axis
ACH