AFLOWT BUF, Руководство по эксплуатации

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1.4.1.4. The flow rate value is calculated only if the following condition is fulfilled:
Q
min

Q,
Where Q
min
– minimal value of the flow rate, m 3
/h;
Q
– current value of the flow rate, m
3
/h.
The recommended value of low flow cutoff corresponds to the flow
meter's sensitivity threshold, m
3
/h.
If Q < Q
min
, condition is fulfilled, the measured flow rate values are
displayed as zero, volume totalizing and pulse transmission to the
universal output are cancelled.
Under Q > Q
max
condition (where Q
max
corresponds to the flow
velocity value of 5 m/s), the metrological characteristics cannot be
ensured. The flow meter measures and displays flow rate values (de-
pending on temperature, liquid density etc.), however, volume totalizing
and logging, as well as pulse transmission to the Universal Output, are
cancelled.
1.4.2. Design
The flow meter's block diagram is shown in Fig.3.
Fig.3. Flow meter's block diagram
BUF-311 flow meter includes the Primary Converter and Secondary
Measuring Converter.
The Primary Converter (CP) is a specially designed measuring pipe
section with one factory-supplied pair of PEAs installed on it.
Secondary Measuring Converter (CS) includes Measurement and
Calculation board, which is responsible for electroacoustic sounding
control, primary and secondary processing of measurement results as
well as for their storing in the memory.