Xylem YSI FDO 4410, Руководство по эксплуатации

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Commissioning, measuring FDO 4410(W)
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ba76197e01 10/2017
2.4 Measuring
Minimum depth of
immersion
Observe the required minimum immersion depth (see chapter 5 T
ECHNICAL
DATA
).
Incident flow The FDO 4410(W) D.O. sensor enables precise measurements without any
incident flow.
However, an incident flow of the sensor membrane improves the responding
behavior of the sensor (see chapter 5 T
ECHNICAL DATA
). The incident flow can
be provided in different ways, e. g.:
 The flow of the water to be measured is sufficient (aeration tank, water
pipe, stream)
 Slowly pull the sensor through the water by hand (lake, container), or

Use a flow aid such as a magnetic stirrer with stirring device (see
chapter 6 W
EAR PARTS AND ACCESSORIES
)
2.5 Function check and user calibration
Factory calibration The FDO 4410(W) is factory calibrated. In the recommended application (see
page 5), the measuring characteristics of the sensor cap remain stable for the
specified service life. Thus, a user calibration is not usually required.
When does a
check or user
calibration make
sense?
A function check or user calibration can be useful in the following special
cases:
 If the measured values appear to be implausible and it is assumed that the
service life of the sensor cap is over
 Routinely within the framework of the company quality assurance.
Check- or
calibration
medium
The check and user calibration take place in water vapor-saturated air. The
suitable conditions are easily provided with the aid of the check and calibra-
tion vessel,
FDO Check
. For this purpose, moisten the sponge inside the ves-
sel. Then insert the sensor in the vessel as far as it will go. The sensor
membrane must be clean and dry for this.
Moisten the sponge:
 Remove the cap (1).
 Take out the sponge (2), wet it, then slightly squeeze it out.
 Insert the sponge again and close the calibration and storage vessel with
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