Xylem wtw MIQ/IDS, Руководство по эксплуатации

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MIQ/IDS Dissolved oxygen
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ba77277d01 01/2024
Evaluation
The result of the check is entered in the log book of the sensor. If the relative
slope is outside the tolerance range (0.90 ... 1.10), the check is assessed as
erroneous.
The basis for the evaluation is the accuracy required by the user. Together with
the nominal value (100 %), this results in a validity range for the check.
If the measured value is within the validity range, no cleaning or calibration is
required.
If the measured value is outside the validity range, the sensor shaft and
membrane should be cleaned, and the check should then be repeated.
Example:
– Required accuracy: ± 2 %.
– In water vapor-saturated air or in air-saturated water, the nominal value for
the relative oxygen saturation (in short: saturation) is 100 %.
– Therefore, the validity scope is 98 ... 102 %
– The check resulted in a measured value of 99.3 %
The measurement error is within the specified validity scope.
No cleaning or calibration is required.
6.2.3 Calibration
The sensor is factory-calibrated. The measuring characteristics of the sensor
cap remain stable for the specified service life. Thus, calibration is usually not
required.
Prepare the check and storage vessel FDO
®
Check
.
The sponge in the
FDO
®
Check
check and storage vessel must be
moist (not wet).
Step 1: The sensor is in the sample.
The sensor is selected in the measured value display.
The procedure is started from the measured value display with
<C> (see IQ S
ENSOR
N
ET
system operating manual).
During calibration, the sensor is in maintenance condition.
All linked outputs remain in their current status.
When operating the sensor in a flow through armature:
Remove the sensor from the flow armature.
Step 2:
Calibration: