Xylem WTW Cu 800 DIN Mode D'emploi page 22

Calibration line of a copper ion sensitive electrode
Measured value
unstable
Slope too low
22
Calibration line of a copper ion sensitive elec-
trode
Meßkettenspannung Electromotive force
0.1
-6
10
What to do if ...
Cause
– Inner junctions not
sufficiently wetted with
bridge electrolyte
– Inner junctions encrusted
– Ground junction
contaminated
– Cable broken
Cause
– Membrane surface
contaminated
– Conditioning time too short
– Standard solutions too old
~29
10-fold concentration change 10-fache Konzentrationsänderung
1 10 100
-5 -4 -3
10
10 10
Remedy
– Fill up bridge electrolyte until the inner
junctions are covered with bridge
electrolyte
– Leave the bridge electrolyte to react on
the inner junctions for some hours until
the crusts have dissolved.
– Rinse ground junction with bridge
electrolyte
– Exchange the electrode
Remedy
– Polish the membrane surface with
polishing strip S/FK (see M
– Extend the conditioning time
– Use new standard solutions
mV
mg/l Cu
1000
-2 -1
10 10
mol/l Cu
AINTENANCE
ba15357d04
Cu 800
2+
2+
)
12/2021