12
©2012 Johnson Level & Tool
8.
Self-Check & Fine Calibration
IMPORTANT:
It is the responsibility of the user to verify the
calibration of the instrument before each use.
Horizontal Line Accuracy (Horizontal)
1. Place the unit on a tripod approximately 5m from a wall.
Secure the laser on the tripod and level the unit.
2. Face the front of the laser to the wall, unlock the laser, and
power on the laser lines. Make a mark on the wall where the
cross-line is displayed. Label this as “A”.
3. Make a mark 2.5m from “A”, along the horizontal laser line,
and label as “M”.
4. Turn the laser until the vertical line meets “M”, and then make a
mark 2.5m from “M”, and 5m from “A”. Label this mark “B”.
Also make a mark on the vertical line where it meets “B”.
5. Measure the height distance between “M” and where the
horizontal laser line currently sits.
6. If e>1mm, the laser accuracy is out of tolerance, and
calibration is necessary.
Horizontal Accuracy Self-Check (Vertical)
1. Stand up two straight poles/boards 5m from each other, or two
walls which are parallel and more than 5m distance.
2. Place the laser on the tripod, and place in the center of the
poles/boards/walls, and level the laser by adjusting the tripod.
3. Power on all laser lines, and make a mark where the cross
laser meets target “A”. Mark this as “A1”.
4. Turn the instrument 180º, so that the cross line meets target
“B”. Mark this as “B1”.
6222H_Manuals 10/2/12 8:54 AM Page 12
