Xylem wtw Br 800 DIN, Operating Manual

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ba15351d04 12/2021
What to do if ... Br 800
Calibration line of a bromide sensitive electrode
What to do if ...
Measured value
unstable
Slope too low
1 0.1
10 100 1000
~58 mV
mg/l Br
-
10 10
10
10
mol/l Br
-
10
Meßkettenspannung
Electromotive force
10-fache Konzentrationsänderung 10-fold concentration change
-5
-6 -4 -3 -2
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