5
OPERATION
26
OPTISENS TUR 2000
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07/2017 - 4001970202 - MA OPTISENS TUR 2000 R01 en
5.2 Calibration
Optical components such as LED and photodiodes can have a small drift during their lifetime.
The windows between the measuring light source/detector and medium to be measured will age
as well due to scratches and more.
5.2.1 Calibration with a signal converter
The sensor requires a 2-point calibration. The sensor is factory calibrated by means of standard
solution and it is ready for use. The operator can perform the field calibration via controller by
means of the sensitivity and zero adjustment.
To avoid alarms on the distributed control system (DCS) when temporarily removing the sensor
(i.e. for maintenance), the signal converter has a hold function. This function "freezes" all
outputs (i.e. the display and the current outputs) of the last measured value.
After starting-up the signal converter, the measuring screen appears. This is the standard
screen which is displayed automatically in the normal operating mode. In this mode the
calibration can be started. Activate the hold function
hold function
hold function
hold function in the first step.
INFORMATION!
Insure that the sensor is clean and free from any deposits on the measurement windows. Please
clean with clear water and a soft cloth as some deposits can be clear and be visible for the
measurement electronics due to infrared operation, but not visible to our eye.
INFORMATION!
It is suggested to verify the sensor periodically and calibrate in case of need to get the requested
accuracy on the specific application.
CAUTION!
•
Never touch or scratch the measurement windows of the sensor.
•
Make sure that the measurement windows are clean and dust-free. If necessary, clean the
measurement windows as described on page 42
•
The device must not be heated by radiated heat (e.g. exposure to the sun) to a electronics
housing surface temperature above the maximum permissible ambient temperature. If it is
necessary to prevent damage from heat sources, a heat protection (e.g. sun shade) has to be
installed.
INFORMATION!
As an indication that the manual hold function is active, the warning sign in the upper left corner
of the display appears. Meanwhile the status messages show checks in progress
checks in progress
checks in progress
checks in progress. For more
details about how to select the manual hold function refer to the signal converter manual.
INFORMATION!
Make sure there are no air bubble infront of the optics as they will be causing measurement
signals due to reflection and light scattering effects and such might cause a wrong reading.
