Xylem 201690, Руководство по эксплуатации

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TriOxmatic
®
690 Maintenance, cleaning, disposal, and replacement
29 ba25314e05 09/2020
5.5 Checking the sensor for freedom from zero-current
The sensor is zero-current free. Therefore, calibration of the sensor in
oxygen-free solution is not provided.
However, it is possible to check the freedom from zero-current
according to DIN EN 25814/ISO 5814. This is advisable if there is any
suspicion of a malfunction.
Test solution 1 g/l aqueous sodium sulfite solution, Na
2
SO
3
(addition of 1 mg/l of a cobalt(II) salt accelerates the removal of oxygen
from the solution)
The sensor should be in operation for at least 1 hour before the
inspection.
Test procedure
8 Fill a new WP 600 membrane cap and screw it on (see section
5.3 C
HANGING THE ELECTROLYTE AND MEMBRANE CAP
).
9 Connect the sensor to the measuring transmitter again.
10 After approx. 60 minutes polarization time, the sensor is ready
for operation.
11 Recalibrate the sensor.
1 Clean the sensor (see section 5.2 C
LEANING THE SENSOR SHAFT
AND MEMBRANE
).
2 On the measuring transmitter, select Saturation (unit %) and
switch to the measured value display.
3 Submerse the sensor in the test solution.
4 Leave the sensor in the test solution for an hour.
5 Read the measured value.