5
Check & Adjust
5.1
Overview
Leica Geosystems instruments are manufactured, assembled and adjusted to
the best possible quality. Quick temperature changes, shock or stress can
cause deviations and decrease the instrument accuracy. It is therefore recom-
mended to check and adjust the instrument from time to time. This check and
adjust can be done in the field by running through specific measurement pro-
cedures. The procedures are guided and must be followed carefully and pre-
cisely as described in the following chapters. Some other instrument errors and
mechanical parts can be adjusted mechanically.
The following instrument errors can be checked and adjusted electronically:
Instrument error
Description
l, t
Compensator longitudinal and transversal index
errors
i
Vertical index error, related to the standing axis
c
Horizontal collimation error, also called line of
sight error
a
Tilting axis error
ATR
ATR zero point error for Hz and V
If the compensator and the horizontal corrections are activated in the instru-
ment configuration, every angle measured in the daily work is corrected auto-
matically. Check whether the tilt correction and the horizontal correction are
turned on.
The results are displayed as errors but used with the opposite sign as correc-
tions when applied to measurements.
The following instrument parts can be adjusted mechanically:
•
Circular level on instrument and tribrach
•
Optical plummet - option on tribrach
•
Allen screws on tripod
To get precise measurements in the daily work, it is important:
•
To check and adjust the instrument from time to time.
•
To take high precision measurements during the check and adjust proce-
dures.
•
To measure targets in two faces. Some of the instrument errors are elimi-
nated by averaging the angles from both faces.
During the manufacturing process, the instrument errors are carefully deter-
mined and set to zero. As mentioned above, these errors can change and it is
highly recommended to redetermine them in the following situations:
Description
Electronic adjustment
Mechanical
adjustment
Precise
measurements
☞
44
Check & Adjust
