Xylem wtw Cl 800 DIN, Operating Manual

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ba15355d04 12/2021
Calibration line of a chloride sensitive electrode Cl 800
Calibration line of a chloride sensitive electrode
What to do if ...
Measured value
unstable
Slope too low
1 0.1 10 100 1000
~58 mV
mg/l Cl
-
10 10 10 10
mol/l Cl
-
10
Meßkettenspannung Electromotive force
10-fache Konzentrationsänderung 10-fold concentration change
-5
-3 -2
-1
-4
Cause Remedy
– Inner junctions not
sufficiently wetted with
bridge electrolyte
– Fill up bridge electrolyte until the inner
junctions are covered with bridge
electrolyte
– Inner junctions encrusted – Leave the bridge electrolyte to react on
the inner junctions for some hours until
the crusts have dissolved.
– Ground junction
contaminated
– Rinse ground junction with bridge
electrolyte
– Cable broken – Exchange the electrode
Cause Remedy
– Membrane surface
contaminated
– Polish the membrane surface with
polishing strip S/FK (see M
AINTENANCE
)
– Conditioning time too short – Extend the conditioning time
– Standard solutions too old – Use new standard solutions