Screen Control - VEGA VEGAMET 842 Handbuch

Application description
VEGAMET 842 • 4 ... 20 mA
eingestellt werden. Zusätzlich muss der Modus "Wechselbetrieb"
aktiv sein.
Note:
Der Index des zuletzt eingeschalteten Relais wird bei Spannungsau-
sfall nicht gespeichert, d. h. nach dem Einschalten des Steuergerätes
startet immer das Relais mit dem kleinsten Index.

10.3 Screen control

In the mechanical pre-cleaning of a hydropower plant, floating solids
are removed with screens or sieves. The subsequent process stages
are thus protected from sedimentation, clogging or abrasion. Large
solids are screened out in the coarse screen, compressed in the
screening press and then disposed of. The fine screen removes the
smaller residues from the waste water. The differential measurement
of the water level in front of and behind the screen determines the de-
gree of pollution and initiates the cleaning of the screen. Two sensors
can be connected simultaneously to the two-channel controller and
the differential measurement can be easily adjusted. Relay outputs
can be used for calculation control and several current outputs for
signal processing.
2
5
Fig. 21: Example of a screen control
1 VEGAMET 842
2 Radar sensor 1
3 Radar sensor 2
4 Screen
5 Upstream water
6 Tailwater
Setup
An application wizard guides you through the most common selection
possibilities. Further application options are available on the corre-
10 Applications and functions
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