Ism - Mettler Toledo InPro 6000 Serie Instructions D'utilisation

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If after such procedures the above mentioned values
are still not reached, replace the OptoCap. If this
doesn't solve the problem too send the sensor to your
local METTLER TOLEDO representative for inspection.
Many sample media contain volatile substances which,
even at very low concentrations, have a clearly
perceptible smell. Similarly to oxygen, these substances
are able to invade the OptoCap. Accordingly, they
become noticeable when interacting with the pigment.
In most cases, such substances have absolutely no
influence on the measuring properties of the sensor.

6.1.3 ISM

DLI: Dynamic Lifetime Indicator
The DLI provides information about the remaining lifetime
of the OptoCap. As long as the DLI is above zero days the
system is within the specified accuracy after a calibration.
If the DLI is zero the OptoCap needs to be replaced.
Contributing factors for ageing of the OptoCap:
• number of measurements
• temperature during measurement
• oxygen concentration during measurement
• number of CIP cycles
• number of SIP cycles
• number of autoclavings
The DLI is calculated in two different ways.
Continuously: With the above parameters an actual
sensor stress is calculated. With each measurement
the sensor load is increased. The accumulated sensor
load divided by the elapsed time is the basis of the cal-
culation of the remaining lifetime.
During calibration: The phase values are compared to
the phase values of the last calibration. Using the
above calculated sensor load and the elapsed mea-
surement time since the last calibration, the remaining
lifetime of the OptoCap is calculated. The calculation
after a calibration gives a higher accuracy of the DLI
compared to the continuous calculation. Thus the DLI
value can be significantly different after a calibration.
Note: For a correct DLI calculation an accurate calibra-
tion is essential.
ACT: Adaptive Calibration Timer
The ACT provides information as to when the next cal-
ibration is required to ensure measurements will re-
main within the specified accuracy. This calculation is
based on the DLI information.
Calibration history
The last four calibrations and the factory calibration da-
ta are stored in the sensor memory. These data can be
read out with a transmitter or with the iSense Asset Suite
software.
The calibration history gives valuable information re-
garding the quality of the calibration and the ageing of
the OptoCap.
InPro 6000 optical O
52 206 256
InPro 6000 Series Optical O
sensors
2
Sensors 12 mm
2
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