Vega VEGAPULS 21 - Rectangular flume flow measurement

16
4 Mounting
VEGAPULS 21 • Two-wire 4 … 20 mA/HART
58351-EN-191014
•
Mounting the sensor on the upstream or inlet side
•
Installationinthecentreoftheumeandverticaltotheliquid
surface
•
DistancetotheoverfalloriceorVenturiume
•
Min. distance to the max. height of damming for optimum accu-
racy: 250 mm (9.843 in)
1)
Detailed project planning data can be found at the channel manufac-
turers and in the technical literature.
Themeasurementcanbeindividuallyconguredfortherespective
umeviaaPC/notebookandPACTware/DTM.Themeasurementcan
beindividuallyconguredfortherespectiveumeviaaPC/notebook
and PACTware/DTM.
Thefollowingexamplesserveasanoverviewforowmeasurement.
3 ... 4 h
max
90°
2
3
1
h
max
≥ 2 x h
max
90°
42 3
≥ 250 mm
(
9.84")
≥ 250 mm
(9.84")
Fig.15:Flowmeasurementwithrectangularume:h
max.
=max.llingofthe
rectangularume
1 Overoworice(sideview)
2 Headwater
3 Tailwater
4 Overfallorice(viewfromtailwater)
Rectangular overfall
1)
At smaller distances the measuring accuracy is reduced, see Technical data.