VEGA VEGAPULS 51K…54K 4 … 20 mA; HART compact sensor - Manual (Page 21)

VEGAPULS 51K … 54K 21
21750-EN-031222
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Mounting and installation
3.4 False echoes
The radar sensor must be be installed at a
location where no installations or inflowing
material cross the radar pulses. The following
examples and instructions show the most
frequent measuring problems and how to
avoid them.
Vessel protrusions
Vessel forms with flat protrusions can make
measurement very difficult due to their strong
false echoes. Baffles mounted above these
flat protrusions scatter the false echoes and
guarantee a reliable measurement.
Intake pipes, i.e. for the mixing of materials -
with a flat surface directed towards the sen-
sor - should be covered with an angled baffle
that scatters false echoes.
Vessel protrusions (ledge)
Vessel protrusions (intake pipe)
Correct Incorrect
Correct Incorrect
Vessel installations
Vessel installations, such as e.g. ladders,
often cause false echoes. Make sure when
planning your measuring location that the
radar signals have free access to the meas-
ured product.
Vessel installations
Correct Incorrect
Ladder
Ladder
Struts
Struts, like other vessel installations, can
cause strong false echoes that overlay the
useful echoes. Small baffles effectively pre-
vent a direct reception of false echoes. These
false echoes are scattered and diffused in
the surrounding space and then filtered out
as "echo noise“ by the measuring electronics.
Struts
Correct Incorrect
Shields