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Initial Operation
confocalDT 2421 / 2422
Performing the Dark Reference
This step is required each time a sensor is changed;
controller warm-up time approx. 30 min.
Cover the sensor with a piece of dark paper. Go to
the
Settings
>
Sensor > Dark reference
menu and click on the
Start
button.
As a check, set the measuring rate to 100 Hz,
Set-
tings
>
Data recording
>
Measuring rate
menu.
Use
Video
to select the video signal display.
Make sure that an exposure time of 10,000 μs is dis-
played. If the signal is not satisfactory, we recommend
cleaning the connections on the controller and on the
fiber optics. For this, use the One-Click Cleaner from the
optional accessories, article 0135032.
Typical signal curve for a dark signal
During the dark reference, there must be no objects
within the measuring range nor ambient light reaching the
sensor under any circumstances. Duration approx. 20 s.
Positioning the Target
Position the target as centrally as possible within the
measuring range.
100 %
50
0
SMR MMR EMR
Dis-
place-
ment
Signal
Sensor
SMR
Measuring range (MR)
Target
The
Range
LED on the front of the controller indicates the
position of the target relative to the sensor.
Flashing red
Dark signal acquisition in
progress
Red
No target present or target
outside of measuring range
Yellow
Target close to mid of
measuring range
Green
Target within the measuring
range
