Xylem wtw NitraVis 705 IQ, Operating Manual

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What to do if...
NitraVis 70x IQ
40 ba75951e03 05/2017
7 What to do if...
"----" display
(invalid measured
value)
Implausible
measured values
Cause Remedy
– User calibration values entered
incorrectly
– *
Sensor check (H2O dest.)
or
*
Zero adjustment
or
*
Sensor check (standard)
defective
– Correct the entry and enter once
again (section 4.3.2)
– Repeat
*
Sensor check (H2O dest.)
or
*
Zero adjustment
or
*
Sensor check (standard)
.
Check conditions, especially clean -
liness (section 4.3.3)
–
Zero adjustment
still erroneous
after several trials
– Contact
service
– Unknown – See log book
Cause Remedy
– Erroneous user calibration – Repeat user calibration. Make sure
the samples for comparison are rep -
resentative.
– Substantial change of test sample
(sample matrix)
– Carry out new user calibration
– Measurement windows dirty – Clean the measurement windows
– Sensor setting wrong – Check and, if necessary, correct the
Measuring mode
,
Measuring loca
-
tion
sensor settings
– Carry out new user calibration
– Optical system maladjusted, e. g.
due to inadmissible mechanical
shock
– Carry out
*
Sensor check (H2O dest.)
or
*
Zero adjustment
or
*
Sensor check (standard)