Bosch GLM 30 Professional Notice Originale page 23

the laser viewing glasses (10) (accessory) and the laser target plate (9) (accessory) or
shade the target area.
Influences on the measurement result
Due to physical effects, the possibility of inaccurate measurements when measuring vari-
ous surfaces cannot be excluded. These include:
– Transparent surfaces (e.g. glass, water)
– Reflective surfaces (e.g. polished metal, glass)
– Porous surfaces (e.g. insulating materials)
– Structured surfaces (e.g. roughcast, natural stone).
If necessary, use the laser target plate (9) (accessory) on these surfaces.
Inaccurate measurements are also possible where the laser is pointed at target surfaces
diagonally.
Layers of air at different temperatures and indirectly received reflections can also influ-
ence the measured value.
Accuracy Check of the Distance Measurement
You can check the accuracy of the measuring tool as follows:
– Choose a measuring section of approx. 3–10 m in length that is permanently un-
changed, the exact length of which is known to you (e.g. room width, door opening).
The measurement should be taken under favourable conditions, i.e. the measuring
section should be indoors and the target surface for the measurement should be
smooth and reflect well.
– Measure the section ten times in succession.
The deviation of the individual measurements from the mean value must not exceed ±
4 mm over the entire measuring section in favourable conditions. Record the measure-
ments in order to be able to compare the accuracy at a later date.
Errors – Causes and Corrective Measures
Cause
Temperature warning (g) flashes, measurement not possible.
Measuring tool is outside of the operating
temperature range of -10 °C to +45 °C.
"Error" indicator in the display.
Target surface is too reflective (e.g. mirror)
or not reflective enough (e.g. black mater-
ial), or ambient light is too bright.
Bosch Power Tools
Corrective measures
Wait until the measuring tool has reached
operating temperature.
Use the laser target plate (9).
1 609 92A 5DZ | (29.01.2020)
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