33
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 30m (98 ft) apart. Orient the
instrument so one axis, either X or Y, is facing the walls.
2
Locate and mark the position of the rotating laser beam on both walls using the target.
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.
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 3mm (1/8 of an inch), no error
exists.
Note
• If the error is grater than 3mm (1/8 of an inch), contact your Topcon dealer.
Cone error
Datum position
Wall
Wall
B
A
Wall
A
Wall
B
Minimum about 30m/98ft
