Bosch GLL 2-50 - Инструкция по эксплуатации - Страница 15

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Bosch Power Tools

1 609 92A 0KJ | (6.5.14)

Working without Automatic Levelling (see figure D)

For work without automatic levelling, push the On/Off switch 

7

 to the 

“   on”

 position. When the automatic levelling is 

switched off, the laser lines flash continuously.

When the automatic levelling is switched off, the measuring 
tool can be held by hand or placed on an inclined surface. In 
cross-line operation, the two laser lines do not necessarily run 
at a right angle to each other.

Levelling Accuracy

Influences on Accuracy

The ambient temperature has the greatest influence. Especially 
temperature differences occurring from the ground upward can 
divert the laser beam.

Because the largest difference in temperature layers is close 
to the ground, the measuring tool should always be mounted 
on a tripod when measuring distances exceeding 20 m. If pos-
sible, also set up the measuring tool in the centre of the work 
area.

Apart from exterior influences, device-specific influences 
(such as heavy impact or falling down) can lead to deviations. 
Therefore, check the accuracy of the measuring tool each 
time before starting your work.

First, check both the height as well as the levelling accuracy of 
the horizontal laser line, then the levelling accuracy of the ver-
tical laser line.

Should the measuring tool exceed the maximum deviation 
during one of the tests, please have it repaired by a Bosch af-
ter-sales service.

Checking the Height Accuracy of the Horizontal Line

For this check, a free measuring distance of 5 m on a firm sur-
face between two walls A and B is required.

– Mount the measuring tool onto a tripod or place it on a firm 

and level surface close to wall A. Switch on the measuring 
tool. Select cross-line operation with automatic levelling.

– Direct the laser against the close wall A and allow the meas-

uring tool to level in. Mark the centre of the point where the 
laser lines cross each other on the wall (point

I

).

– Turn the measuring tool by 180 °, allow it to level in and 

mark the cross point of the laser lines on the opposite wall 
B (point

II

).

– Without turning the measuring tool, position it close to wall 

B. Switch the measuring tool on and allow it to level in.

– 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.

– 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

max

 is calculated as fol-

lows:
d

max

= double distance of the walls x 0.3 mm/m

Example: With a 5 metre distance between the walls, the 
maximum deviation must not exceed 
d

max

= 2 x 5 m x 0.3 mm/m = 3 mm. Thus, the marks must not 

be more than 3 mm apart.

A

B

5 m

A

B

180˚

A

B

d

180˚

A

B

OBJ_BUCH-817-005.book  Page 15  Tuesday, May 6, 2014  10:15 AM