Bosch GLL 30 G Original Instructions Manual page 11

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 be-
fore beginning work.
First check the height accuracy and levelling accuracy of the horizontal laser line, then
the levelling accuracy of the vertical laser line.
If the measuring tool exceeds the maximum deviation in one of the checks, it should be
sent to the Bosch after-sales service 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 the holder or a tripod, or place it on a firm,
level surface. Switch on the measuring tool.
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).
A
180°
Bosch Power Tools
B
5 m
English | 11
B
1 609 92A 4F1 | (28.06.2018)