FlowCERT

Point of Measurement
The transducer must be above the maximum head P704 by at least the near
blanking distance P107.
For Suppressed Rectangular, Trapezoidal and V-notch, weirs, the head is
measured upstream at a minimum distance of 3 times maximum head
from the weir plate to ensure the surface of the liquid is not affected by
turbulence or drawdown. (See DRWG. 1)
In the case of a Venturi flume the point of measurement should be 150 mm
upstream from the beginning of the converging section and for a Parshall
flume 2/3 the length of the converging section upstream of the throat
section. See DRWG 2 and 3)
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