16
4 Mounting
VEGAPULS C 11 • Two-wire 4 … 20 mA
58340-EN-200806
•
Mounting the sensor on the upstream or inlet side
•
Installation in the centre of the flume and vertical to the liquid
surface
•
Distance to the overfall orifice or Venturi flume
•
Min. distance to the max. height of damming for optimum accu-
racy: 250 mm (9.843 in)
2)
Detailed project planning data can be found at the channel manufac-
turers and in the technical literature.
The following examples serve as an overview for flow measurement.
3 ... 4 h
max
90°
2
3
1
h
ma
x
≥ 2 x
h
ma
x
90°
4
2
3
≥ 250 mm
(9.84
")
≥ 250 mm
(9.84
")
Fig. 15: Flow measurement with rectangular flume: h
max.
= max. filling of the
rectangular flume
1 Overfall orifice (side view)
2 Upstream water
3 Tailwater
4 Overfall orifice (view from tailwater)
Rectangular overfall
2)
At smaller distances the measuring accuracy is reduced, see "Technical
data".
