Automatic Levelling; Accuracy Check Of The Measuring Tool; Influences On Accuracy; Checking The Height Accuracy Of The Horizontal Line - Bosch GCL 2-15 Professional Original Instructions Manual

20 | English
Sequence of actions
Press the laser line mode but-
ton (5) once
Press the laser line mode but-
ton (5) twice
Press the laser line mode but-
ton (5) three times
The laser lines continuously flash slowly in "working without
automatic levelling" mode.
If, during work with automatic levelling, you switch to "work-
ing without automatic levelling" mode (on/off switch (8) in
position " On"), the first combination option of this
mode's indicators is always activated.

Automatic Levelling

Working with Automatic Levelling (see figures B1–E1)
Position the measuring tool on a level, firm surface or attach
it to the rotating mount (13).
For work with automatic levelling, slide the on/off switch (8)
to the " On" position.
The automatic levelling function automatically levels irregu-
larities within the self-levelling range of ±4°. The measuring
tool has been levelled as soon as the laser beams stop flash-
ing.
If automatic levelling is not possible, e.g. because the sur-
face on which the measuring tool stands deviates by more
than 4° from the horizontal plane, the laser beams will flash
quickly.
If this is the case, set up the measuring tool in a level position
and wait for the self-levelling to take place. As soon as the
measuring tool is within the self-levelling range of ±4°, the
laser beams will light up continuously.
In case of ground vibrations or position changes during oper-
ation, the measuring tool is automatically levelled again.
Upon levelling, check the position of the laser beams with re-
gard to the reference points to avoid errors arising from a
change in the measuring tool's position.
Working without Automatic Levelling (see figure F1)
For work without automatic levelling, slide the on/off
switch (8) to the " On" position. When automatic levelling
is switched off, the "working without automatic levelling" in-
dicator (3) lights up red and the laser lines flash slowly and
continuously.
Switching off the automatic levelling function allows you to
hold the measuring tool freely in your hand or place it on a
sloping surface. This means that the laser beams no longer
necessarily run perpendicular to one another.
1 609 92A 4HE | (09.08.2018)
Horizontal line Vertical line
mode mode
● –
– ●
● ●
cross-line mode

Accuracy Check of the Measuring Tool

Influences on Accuracy

The largest influence is exerted by the ambient temperature.
In particular, temperature differences that occur from the
ground upwards can refract the laser beam.
Since the temperature stratification is greatest at ground
level, you should mount the measuring tool on a tripod and
position it in the centre of the work surface, wherever this is
possible.
In addition to external influences, device-specific influences
(e.g. falls or heavy impacts) can also lead to deviations. For
this reason, check the levelling accuracy each time before
beginning work.
First check the height accuracy and levelling accuracy of the
horizontal laser line, then the levelling accuracy of the ver-
tical laser line.
If the measuring tool exceeds the maximum deviation in one
of the checks, it should be sent to the Bosch after-sales ser-
vice for repair.

Checking the Height Accuracy of the Horizontal Line

For this check, you will need a free measuring distance of
5 m on firm ground between two walls (designated A and B).
– Mount the measuring tool close to wall A on a tripod, or
place it on a firm, level surface. Switch on the measuring
tool. Select cross-line mode with automatic levelling.
A
– Aim the laser at the closer wall A and allow the measuring
tool to level in. Mark the middle of the point at which the
laser lines cross on the wall (point I).
Point mode "Working without
automatic level-
ling" indicator (3)
–
Red
–
Red
–
Red
5 m
Bosch Power Tools
Figure
F1
B