Endress+Hauser Oxymax W COS51D, Руководство по эксплуатации

Страница: 21 / 36

Oxymax W COS51D Maintenance
Hauser 21
7 Maintenance
Maintenance work must carried out at regular intervals. To ensure that it is carried out, we
recommend you enter the maintenance dates into an operations logbook or in an operations
calendar in advance.
The maintenance cycle primarily depends on:
• the system
• the installation conditions and
• the medium in which measurement is taking place.
The following activities must be carried out:
• Cleaning the sensor
(In particular when the membrane is soiled)
• If necessary, replacing wear and tear materials:
– sealing ring
– electrolyte
– membrane cap
• Check the measuring function:
– Remove the sensor from the medium.
– Clean and dry the membrane.
– After about 10 minutes, measure the oxygen saturation index in air (without recalibration).
– The measured value should be near to 102% SAT
• Recalibration.
7.1 Cleaning
The measurement can be corrupted by sensor fouling or malfunction, e.g.:
• Coatings on the sensor membrane
--> cause longer response times and a reduced slope under certain circumstances.
• Soiling or poisoning of the electrolyte
--> causes longer response times and false measurement.
• Coatings on the electrodes
--> cause longer response times and false measurement.
To ensure reliable measurement, the sensor must be cleaned at regular intervals. The frequency and
intensity of the cleaning operation depend on the measuring medium.
7.1.1 Cleaning the sensor surface
Clean the sensor surface:
• before every calibration
• at regular intervals during operation as necessary
• before returning it for repairs.
Depending on the type of soiling, proceed as follows:
"
Caution!
After cleaning, rinse the sensor with copious amounts of clean water.
!
Note!
For regular automatic sensor cleaning, we recommend equipping the measuring point with a
fully-automatic cleaning system, e.g. Chemoclean (see accessories).
Type of soiling Cleaning
Salt deposits Immerse the sensor in drinking water or in 1-5% hydrochloric acid
for a few minutes. Afterwards, rinse it with copious amounts of water.
Dirt particles on the sensor body
(not cap!)
Clean the sensor body mechanically with water and a suitable brush.
Dirt particles on the membrane cap or the
membrane Clean with water and a soft sponge.