1.4.1.4. The flow rate value is calculated only if the following condition is fulfilled:
Q
min
≤
Q,
(2)
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
flowmeter'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 uni-
versal output are cancelled.
Under Q > Q
max
condition (where Q
max
corresponds to the flow ve-
locity value of 5 m/s), the metrological characteristics cannot be en-
sured. The flowmeter measures and displays flow rate values (depend-
ing on temperature, liquid density etc.), however, volume totalizing and
logging, as well as pulse transmission to the Universal Output N1, are
cancelled.
1.4.2. Design
The flowmeter's block diagram is shown in Fig. 2.
Fig. 2. Flowmeter's block diagram
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