CHC
CTS-112R4 user manual
102
5)
Repeat the inspection and adjusting steps to be sure the adjustment is correct.
6)
Replace the protective cover.
15.9.
Instrument constant (K)
Instrument constant has been checked and adjusted in the factor, K=0. It changes seldom, and it is
suggested to check one or two times every year. The inspection should be made on the base line, also
can be made according to the following method.
Inspection
1)
Mount and level the instrument on point A in a plain place. Use the vertical hair to mark point B and
point C on the same line with the distance of 50 m on the same line and set the reflector accurately.
2)
After setting temperature and air pressure in the instrument, measure the horizontal distance of AB
and AC accurately.
3)
Set the instrument on Point B and center it accurately, measure the Horizontal Distance of BC
accurately.
4)
Then you can get the instrument constant: K
＝
AC
－
(AB
＋
BC)
K should be closed to 0, if
｜
K
｜
> 5 mm, the instrument should be strictly inspected in the
standard baseline site and adjusted according the inspection value.
Adjustment
If strict inspection approves that the instrument constant K has changed and is not closed to 0. If the
operator wants to adjust, should set stadia constant according the constant K (power on pressing [F1]).
1)
Set the direction by using the Vertical Hair to make Point A,B,C on the same line strictly. On point
there must be fixed and clear centering mark.
2)
Whether the prism center of point B coincide with the Instrument center the B is the important to
inspect the accuracy. So, on point B tripod or tribrach compatible should be used. That will decrease
the difference.
