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Assembly
optoNCDT 1900 / Profinet
5.1.2
Interferences
5.1.2.1
Ambient Light
Thanks to their integrated optical interference filters, the optoNCDT 1900 laser-optical sensors offer outstanding performance in sup-
pressing ambient light. However, ambient light disturbances can occur with shiny measuring objects and at a reduced measuring rate.
In these cases it is recommended to provide shielding against ambient light or to switch on the
Background suppression
function.
This applies in particular to measurement work performed in the vicinity of welding devices.
5.1.2.2
Color Differences
Because of intensity compensation, color difference of targets affect the measuring result only slightly. However, such color differ-
ences are often combined with different penetration depths of the laser light into the material. Different penetration depths then result
in apparent changes of the measuring spot size. Therefore color changes in combination with penetration depth changes may lead to
measurement uncertainties.
5.1.2.3
Thermal Influences
When the sensor is commissioned, a warm-up time of at least 20 minutes is required to achieve uniform heat distribution in the sensor.
If measurement is performed in the µm accuracy range, the effect of temperature fluctuations on the sensor holder must be consid-
ered.
Rapid temperature changes are not detected immediately due to the damping effect of the sensor’s heat capacity.
5.1.2.4
Mechanical Vibrations
If a high degree of resolution in the µm range is required, the sensor and target must be mounted on a stable surface that is damped
against vibrations.
5.1.2.5
Motion Blur
Fast moving targets and a low measuring rate may also cause motion blurring. Therefore, always select a high measuring rate for
high-speed operations to prevent errors.
