Endress+Hauser Topcal S CPC310, Руководство по эксплуатации

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Maintenance
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Please clean fouling on the pH glass electrodes as follows:
• Oily and greasy deposits:
Clean with hot water or tempered detergent (grease remover, e.g. alcohol, acetone, washing up
liquid where applicable).
#
Warning!
When using the following cleaning agents, make sure to protect your hands, eyes and clothing!
• Deposits of lime and metal hydroxide:
Remove deposits with diluted hydrochloric acid (3 %) and then rinse carefully with large amounts
of clear water.
• Deposits containing sulfide (from flue gas desulfurizing or sewage treatment plants):
Use a mixture of hydrochloric acid (3 %) and thiocarbamide (usual commercial) and then rinse
carefully with large amounts of clear water.
• Deposits containing protein (e.g. food industry):
Use a mixture of hydrochloric acid (0.5 %) and pepsin (usual commercial) and then rinse carefully
with large amounts of clear water.
• Fibers, suspended substances:
Water under pressure, poss. with surface-active agents
• Light biological deposits:
Water under pressure
Redox electrodes
Carefully clean the metal pins and surfaces mechanically.
!
Note!
After mechanical cleaning, the redox sensor can require several hours conditioning time. For this
reason, check calibration after one day.
ISFET sensors
• When cleaning ISFET sensors, do not use any acetone as this can damage the material.
• After cleaning with compressed air, ISFET sensors need approx. 5 ... 8 minutes until the
closed-control loop is reestablished and the measured value is adjusted to the real value.
In certain circumstances, you can clean blocked diaphragms mechanically (does not apply to
ISFET sensors, teflon diaphragms and open ring junction electrodes):
• Use a small key 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 from 15
°
to 165
°
to the horizontal is allowed (with the exception of ISFET sensors).
• Horizontal installation or installation with the plug-in head pointing downwards is not permitted.
a0006756.eps
Fig. 63: Permitted angle of installation for glass electrodes
> 15°
> 15°