DeWalt DW074 Guide D'utilisation page 14

FIG. 15
BEAM
A
L
5. Turn the entire laser unit 180º so the X-axis points directly
toward the opposite wall.
6. Allow the laser unit to self-level, and mark and measure points
AA and BB on the walls as shown in Figure 16.
FIG. 16
LASER UNIT ROTATED 180˚
BEAM
AA
L
7. Calculate the total error using the equation:
Total Error = (AA – A) – (BB– B)
8. Compare total error to the allowable limits shown in the following
table.
Distance between walls
L = 50 ft. (15.3 m)
L = 75 ft. (22.9 m)
B
L = 100 ft. (30.5 m)
LEVEL CALIBRATION CHECK (Y-AXIS)
Repeat the procedure above, but with the laser unit positioned so
the Y-axis is pointed directly toward the walls.
PLUMB ERROR CHECK (FIG. 17)
1. Using a standard plumb bob as
a reference, mark the top and
bottom of a wall (Be sure to
mark the wall and not the floor
and ceiling.)
2. Position the rotary laser securely
on the floor approximately 1 m
(3 ft.) from the wall.
3. Turn the laser on and level it
using the arrow buttons to center
BB
the bubble. Put the unit in low
speed rotation for maximum vis-
ibility, making sure the beam
passes through the mark on the
bottom of the wall. Recheck the
bubble position to confirm it is
still centered.
4. If the center of the beam lines up with the marks at the bottom
and top of the wall, the laser is properly calibrated.
NOTE: This check should be done with a wall no shorter than the
tallest wall for which this laser will be used.
12
Allowable Error
1/4" (6 mm)
3/8" (9 mm)
1/2" (12 mm)
FIG. 17
MARKS
ON
WALLS