48
Horizontal Rotation Cone Error
Perform the following check after completing “Horizontal Calibration” on the previous
page.
1 Set up the laser centered between two walls approximately 40m (131 ft) apart. Orient the
instrument so one axis, either X or Y, is facing the walls. Grade should be set to 0.00% in both
axes.
2 Locate and mark the position of the rotating laser beam on both walls using the LS-70A laser
sensor.
3 Turn off the instrument and move the instrument closer to wall A (1m to 2m /3 ft to 6 ft).
Do not change the axis orientation of the instrument. Turn the instrument on.
4 Again locate and mark the position of the rotating laser beam on both walls using the LS-70A
laser sensor.
5 Measure the distance between the first and second marks on each wall.
6 If the difference between each set of marks is less than ±4mm (±5/32 of an inch), no error
exists.
If the difference between [wall A]-side and [wall B]-side exceeds ±4mm (±5/32 of an
inch), contact your dealer or Topcon.
Minimum about 40m/131ft
Cone error
Datum position
Wall
A
Wall
A
Wall
B
Wall
B
To Next Page
Loading...
