Endress+Hauser Liquisys M CPM223, Руководство по эксплуатации

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Liquisys M CPM223/253 Maintenance
Hauser 79
7.2.2 Cleaning the pH/Redox sensors
Please clean contamination on the glass electrodes as follows:
• Oily and greasy films:
Clean with detergent (grease dissolvers, such as alcohol, acetone, poss. washing-up liquids).
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Warning!
When using the following cleaning agents, make sure to protect your hands, eyes and clothing!
• Lime and metal hydroxide layers:
Dissolve layers with diluted hydrochloric acid (3 %) and then rinse carefully with a lot of clear
water.
• Layers containing sulphide (from flue gas desulphurising or sewage treatment plants):
Use mixture of hydrochloric acid (3 %) and thiocarbamide (usual commercial) and then rinse
carefully with a lot of clear water.
• Layers containing proteins (e.g. food industry):
Use mixture of hydrochloric acid (0.5 %) and pepsin (usual commercial) and then rinse carefully
with a lot of clear water.
Clogged diaphragms can be cleaned mechanically (does not apply to Teflon diaphragms and open
ring junction electrodes):
• Use a small warding file.
• Only file in one direction.
Air bubbles in the electrode:
• Air bubbles can indicate incorrect mounting. For this reason check the orientation.
• The range 15 to 165 to the horizontal is allowed.
• Not permitted: horizontal installation or installation with the plug-in head pointing downwards.
C07-CPM2x3xx-05-06-00-xx-006.eps
Fig. 48: Permitted angle of installation for glass electrodes
Redox electrodes:
Carefully clean the metal pins or surfaces mechanically.
!
Note!
After mechanical cleaning, the redox sensor can require several hours conditioning time. For this
reason, check the calibration after a day.
7.2.3 Maintaining digital sensors
Proceed as follows to maintain the digital sensors with Memosens functionality:
1. If an error occurs or the sensor has to be replaced according to the maintenance schedule, take
a new or precalibrated sensor from the lab.
In the lab, a sensor is calibrated under optimum external conditions to ensure a higher quality
of measurement.
2. Remove the contaminated sensor and insert the new sensor.
3. A calibration is necessary if you are using a sensor which was not pre-calibrated.
4. The sensor data are automatically taken by the transmitter. No release code is required.
5. Measurement is continued.
6. Take the used sensor back to the lab. Here you can possibly make the sensor ready for use again
without the measuring point having to suffer downtime.
– Clean the sensor. For this purpose, use the cleaning agent indicated for the sensor.
– Inspect the sensor for cracks or other damage.
– Regenerate the sensor if it is not damaged. Store it for 24 hours in a 3M KCl solution.
– Recalibrate the sensor for the next use.
> 15° > 15°