VEGA VEGASON S 61 - Handbuch (Seite 26)

Socket
The mounting socket should preferably be dimen-
sioned to allow the lower edge of the transducer to
protrude at least 10 mm out of the socket.
ca. 10 mm
Fig. 21: Recommended socket mounting
Vessel installations
The ultrasonic sensor should be installed at a
location where no installations cross the ultrasonic
beam.
Vessel installations such as e.g. ladders, level
switching, heating spirals, struts etc. can cause
faulse echoes which can superimpose the useful
echo.
If there are existing vessel installations, a false
echo storage should be carried out during setup.
If large vessel installations such as struts or
supports cause false echoes, these can be
attenuated through supplementary measures.
Small, inclined sheet metal or plastic baffles above
the installations scatter the ultrasonic signals and
avoid direct false echoes.
Fig. 22: Cover smooth profiles with deflectors
Agitators
If there are agitators in the vessel, a false echo
storage should be carried out with the agitators in
motion. This ensures that the interfering reflections
from the agitators are saved with the blades in
different positions.
Inflowing medium
Do not mount the instruments in or above the filling
stream. Make sure that you detect the product
surface and not the inflowing product.
Fig. 23: Inflowing liquid
Foam
Through the action of filling, stirring and other
processes in the vessel, dense foams which
considerably damp the emitted signals may form
on the product surface.
If foams are causing measurement errors, the
sensor should be used in a standpipe or, alter-
natively, the more suitable guided radar sensors
(TDR) should be used.
Guided radar is not influenced by foam generation
and is particularly suitable for such applications.
Air turbulence
If there are strong air currents in the vessel, e.g.
due to strong winds in outdoor installations, or
because of air turbulence, e.g. by cyclone ex-
haustion you should mount VEGASON S 61 in a
standpipe or use a different measuring principle, e.
g. radar or guided radar (TDR).
26 VEGASON S 61
Mount
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