Xylem wtw NO 800 DIN, Operating Manual

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What to do if ... NO 800
What to do if ...
Measured value
unstable
Slope too low
Technical data
Measuring range
Reproducibility
pH range
Temperature range
Membrane resis-
tance
Length
Diameter
Cause Remedy
– Inner junctions not
sufficiently wetted with
bridge electrolyte
– Fill up bridge electrolyte until the inner
junctions are covered with bridge
electrolyte
– Junctions encrusted – Leave the bridge electrolyte to react on
the junctions for some hours until the
crusts have dissolved.
– Cable broken – Exchange the electrode
Cause Remedy
– Conditioning time too short – Extend the conditioning time
– Standard solutions too old – Use new standard solutions
– Junctions encrusted – Leave the bridge electrolyte to react on
the junctions for some hours until the
crusts have dissolved.
– Electrode defective – Exchange the electrode
0.4 ... 62,000 mg/l NO
3
-
(1 x 10
-6
... 1 mol/l NO
3
-
)
± 2 %
2.5 ... 11 (see section I
NTERFERENCES
)
0 ... 40 °C
1 to 5 M
Ω
170 mm (including 50 mm connection head)
Shaft: 12 mm
Connection head 16 mm