Checking The Levelling Accuracy Of The Horizontal Line - Bosch GLL 3-15 Professional Original Instructions Manual

OBJ_BUCH-2194-001.book Page 9 Monday, May 19, 2014 12:24 PM
– Without turning the measuring tool, position it close to wall
B. Switch the measuring tool on and allow it to level in.
A
– Align the height of the measuring tool (using a tripod or by
underlaying, if required) in such a manner that the cross
point of the laser lines is projected against the previously
marked point II on the wall B.
A
d
– Without changing the height, turn around the measuring
tool by 180°. Direct it against the wall A in such a manner
that the vertical laser line runs through the already marked
point I. Allow the measuring tool to level in and mark the
cross point of the laser lines on the wall A (point III).
– The difference d of both marked points I and III on wall A
indicates the actual height deviation of the measuring tool.
The maximum permitted deviation d
follows:
d = double the distance between the walls x 0.2 mm/m
max
Example: If the distance between the walls is 5 m, the maxi-
mum deviation is
d = 2 x 5 m x 0.2 mm/m = 2 mm. The marks must there-
max
fore be maximum 2 mm apart.

Checking the Levelling Accuracy of the Horizontal Line

For the check, a free surface of approx. 5 x 5 metres is re-
quired.
– Mount the measuring tool in the middle between walls A
and B on the rotating platform or a tripod, or place it on a
firm, flat surface. Switch on the measuring tool in the mode
with automatic levelling. Switch on horizontal mode and
allow the measuring tool to level in.
Bosch Power Tools
B
– At a distance of 2.5 metres from the measuring tool, mark
the centre of the laser line (point I on wall A and point II on
wall B) on both walls.
B
A
180°
– Set up the measuring tool 5 metres away turned by 180°
and allow it to level in.
– Align the height of the measuring tool (using a tripod or by
can be calculated as
max
underlaying, if required) in such a manner that the centre
of the laser line is projected exactly against the previously
marked point II on wall B.
– Mark the centre of the laser line as point III (vertically
above or below point I) on the wall A.
– The difference d of both marked points I and III on wall A
indicates the actual deviation of the measuring tool from
the level plane.
The maximum permitted deviation d
follows:
d
max
Example: If the distance between the walls is 5 m, the maxi-
mum deviation is
d
max
fore be maximum 2 mm apart.
A
B
max
= double the distance between the walls x 0.2 mm/m
= 2 x 5 m x 0.2 mm/m = 2 mm. The marks must there-
1 609 92A 0MG | (19.5.14)
English | 9
B
can be calculated as