Johnson Level & Tool Mfg. 40-6656 - Manual (Page 11)

©2013 Johnson Level & Tool 11
5. Measure the distance ‘e’ from Dot ‘M’ to the laser line, as per
the Figure.
6. If ‘e’ > 1.5mm, the instrument is out of tolerance and must be
calibrated.
Horizontal Accuracy Self-Check (Longitudinal)
1. Set up two survey-staffs, OR use two walls, both 5 Meters
from each other (or further).
2. Set the instrument on a level tripod, and center between the
two survey staffs/walls.
3. Power on all laser lines, and move the laser until the cross dot
projects on staff/wall A. Make a mark and label as ‘A1’.
4. Rotate the instrument 180° and make the cross dot project on
staff/wall B. Make a mark and label as ‘B1’.
7048H_Manuals 6/19/13 10:53 AM Page 11