Endress+Hauser CCS50D, Operating Instructions Manual

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CCS50D Product description
Hauser 9
silver chloride. Electron donation at the gold cathode and electron acceptance at the silver
anode cause a current to flow which is proportional to the concentration of chlorine dioxide in
the medium. This process does not depend on the pH value over a wide range.
The transmitter uses the current signal to calculate the measured variable for concentration in
mg/l (ppm).
3.1.2 Effects on the measured signal
pH value
pH dependency
pH value Result
< 3.5 Chlorine is produced if chloride (Cl
-
) is present in the medium at the same time. The strong cross-sensitivity
to chlorine dioxide causes an increase in the measured value.
3.5 to 9 The pH value does not affect measurement of the chlorine dioxide concentration in the medium.
> 9 Chlorine dioxide is unstable and decomposes.
Flow
The minimum flow velocity of the membrane-covered measuring cell is 15 cm/s (0.5 ft/s).
• When using the Flowfit CCA151 flow assembly, this corresponds to a flow rate of
5 l/h (1.3 gal/h).
• When using the CCA250 flow assembly, this corresponds to a flow rate of
30 l/h (7.9 gal/h) (upper edge of float at the height of the red bar mark).