Bosch GLL50-40G Operating/Safety Instructions Manual page 13

– The discrepancy d between the two marked
points I and III on wall A reveals the actual
height deviation of the measuring tool.
The maximum permitted deviation on the
measuring distance of 2 × 16 ft = 36 ft (2 ×
5 m = 10 m) is as follows:
32 ft x ±0.0048 in/ft = ±3/16 in (0.154 in)
(10 m × ±0.4 mm/m = ±4 mm)
The discrepancy d between points I and III
must therefore amount to no more than 4
mm.
Checking the Leveling Accuracy
of the Horizontal Line
For this check, you will need a free area of
16 × 16 ft (5 × 5 m).
– Mount the measuring tool in the middle be-
tween walls A and B on a tripod, or place it
on a firm, level surface. Switch on the mea-
suring tool and select horizontal operation.
Allow the measuring tool to level in.
A
– At a distance of 8 ft (2.5 m) from the mea-
suring tool, mark the center of the laser line
on both walls (point I on wall A and point II
on wall B).
A
2610059938 GLL50-40G 02-21.indd 13
B
B
-13-
– Set up the measuring tool at a 16 ft (5 m)
distance and rotated by 180° and allow it to
level in.
– Align the height of the measuring tool (us-
ing the tripod or by placing objects under-
neath as required) so that the center of the
laser line exactly hits the previously marked
point II on wall B.
– Mark the center of the laser line on wall A as
point III (vertically above or below point I).
– The discrepancy d between the two marked
points I and III on wall A reveals the actual
horizontal deviation of the measuring tool.
The maximum permitted deviation on the
measuring distance of 2 × 16 ft = 32 ft (2 ×
5 m = 10 m) is as follows:
32 ft x ±0.0048 in/ft = ±3/16 in (0.154 in)
(10 m × ±0.4 mm/m = ±4 mm)
The discrepancy d between points I and III
must therefore amount to no more than 4
mm.
Checking the Leveling Accuracy
of the Vertical Line
For this check, you will need a door opening
(on solid ground) which has at least 8 ft (2.5
m) of space either side of the door.
– Place the measuring tool 8 ft (2.5 m) away
from the door opening on a firm, flat sur-
face (not on a tripod). Switch on the mea-
suring tool and select vertical operation.
Aim the laser line at the door opening and
allow the measuring tool to level in.
– Mark the center of the vertical laser line on
the floor of the door opening (point I), 16
ft (5 m) away on the other side of the door
opening (point II) and on the upper edge of
the door opening (point III).
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