Flexim FLUXUS F704**-A2 Series, User Manual

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FLUXUS F70x 9 Basic Measurement
96 UMFLUXUS_F7V4-6-2EN, 2017-10-01
9 Basic Measurement
9.6.1 Fine Adjustment of the Transducer Distance
In case of large deviations, check if the entered parameters are correct or repeat the measurement at a different point on
the pipe.
Repeat the steps for all channels on which a measurement is being made. The measurement will be started automatically
afterwards.
9.6.2 Consistency Check
If a wide range for the sound speed has been entered in the program branch
Parameter
or the exact parameters of the
medium are not known, a consistency check is recommended.
The transducer distance can be displayed during measurement by scrolling with key
.
The optimum transducer distance is calculated on the basis of the measured sound speed. It is therefore a better approx-
imation than the first recommended value which had been calculated on the basis of the sound speed range entered in the
program branch
Parameter
.
If the difference between the optimum and the entered transducer distance is less than specified in Tab. 9.1, the measure-
ment is consistent and the measured values are valid. The measurement can be continued.
If the difference is greater, adjust the transducer distance to the displayed optimum value. Afterwards, check the signal
quality and the signal amplitude bar graph (see section 9.6.1). Press ENTER.
If the displayed transducer distance is adjusted, press ENTER.
The measuring for the positioning of the transducers is started.
The amplitude of the received signal is displayed by the bar graph
S=
.
If the LED of the measuring channel lights green, the signal is sufficient for a measurement
(FLUXUS F709).
If the LED of the measuring channel lights red, the signal is not sufficient for a measure-
ment (FLUXUS F709).
Shift a transducer slightly within the range of the recommended transducer distance
• FLUXUS F704, F705: until the bar graph reaches its max. length (max. 6 squares)
• FLUXUS F709: until the LED of the measuring channel lights green.
The following quantities can be displayed in the upper line by pressing key and in the
lower line by pressing key :
•
■ <> ■ =:
transducer distance
•
time
: Transit time of the measuring signal in μ s
•
S=
: signal amplitude
•
Q=
: signal quality, bar graph has to have max. length
If the signal is not sufficient for measurement,
Q= UNDEF
will be displayed.
After the precise positioning of the transducers, the recommended transducer distance is
displayed again.
Enter the actual (precise) transducer distance. Press ENTER.
The optimum transducer distance (here: 50.0 mm) is displayed in the upper line in paren-
theses, followed by the entered transducer distance (here: 54.0 mm). The latter value has
to correspond to the adjusted transducer distance. Press ENTER to optimize the transduc-
er distance.
Transd. Distance
A:
54 mm !
S=

A:

<>

=54 mm!
S= ■■■■■■
Q= ■■■■■■■■■■■■
time= 94.0 μ s
Q= ■■■■■■■■■■■
Transd. Distance?
53.9 mm
L=(50.0) 54.0 mm
54.5 m3/h