Xylem WTW UV 701 IQ SAC, Инструкция по эксплуатации

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UV 70x IQ SAC
Measurement / Operation
25 ba77046e02 05/2017
measured value at different points (see section 4.1):

User calibration (see section 4.3.2)

Sensor check/
Zero adjustment
(see section 4.3.3).
An overview diagram of the calibration procedures can be found on page 4 - 31.
User calibration

Parameter SAC (
SAC 254, dissolved
,
SAC 254, total
):
Due to the measuring principle, no user calibration is required for the param
-
eter SAC (see chapter 10 A
PPENDIX
: G
LOSSARY
).
If implausible measured values occur, a user calibration with reference val
-
ues may be useful, depending on the cause (see chapter 7 W
HAT TO DO IF
...).

Correlated parameters (
CODds correl.
,
CODto correl.
,
TOC correl.
,
BOD cor
-
rel.
,
DOC correl.
)
A user calibration establishes a correlation between the SAC value and
another parameter.
Recalibration after a
change of the
measuring location
(only for correlated
parameters)
Sensor check (H2O
dest.)
The characteristics of a sensor and thus the measured values provided by it
change in the course of time.
The reasons for this can be the aging of the sensor, or contamination or
mechanical damage of the sensor. Contamination or mechanical damage in the
area of the measuring chamber or on the measurement windows affect the
measured values.
A
Sensor check (H2O dest.)
determines the condition of the sensor. By checking
the sensor with the aid of the
Sensor check (H2O dest.)
you can rapidly see any
changes of the sensor and whether it needs to be cleaned or if any other actions
have to be taken.
A
Sensor check (H2O dest.)
should be carried out twice per year at regular inter
-
vals. An extraordinary
Sensor check (H2O dest.)
should be carried out if you
suspect that the sensor has been damaged such as by mechanical shock, or if
the measured values do not seem plausible.
Each time after the application or measurement location was
changed, we recommend to carry out a
Zero adjustment
(and, if the
Sensor check (H2O dest.)
was not successful, also a
Zero adjust
-
ment
with user calibration if necessary).
The data of the user calibration are stored in the IQ S
ENSOR
N
ET
controller and thus assigned to the measuring location (not to the
sensor). The calibration data of the
Zero adjustment
are stored in
the sensor.
In spectroscopy, even very small contamination that is not visible to
the eye can considerably affect the measured value.
The proper and thorough cleaning of the sensor is the basis for reli
-
able measurement data.