User Manual

48 VEGAPULS 42 and 44 – 4 … 20 mA
Mounting and installation
4.4 False echoes
The installation location of the radar sensor
must be selected such that no installations or
inflowing material cross the radar impulses.
The following examples and instructions
show the most frequent measuring problems
and how to avoid them.
Vessel protrusions
Vessel forms with flat protrusions can, due to
their strong false echoes, greatly effect the
measurement. Shields above these flat pro-
trusions scatter the false echoes and guaran-
tee 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 a sloping shield
that will scatter false echoes.
Vessel protrusions (slope)
Vessel protrusions (intake pipe)
Correct Wrong
Correct Wrong
Vessel installations
Vessel installations such as, for example, a
ladder, often cause false echoes. Make sure
when planning your measuring location that
the radar signals have free access to the
measured product.
Vessel installations
Correct Wrong
Ladder
Ladder
Struts
Struts, like other vessel installations, can
cause strong false echoes that are superim-
posed on the useful echoes. Small shields
effectively hinder a direct false echo reflec-
tion. These false echoes are scattered and
diffused in the area and are then filtered out
as "echo noise“ by the measuring electronics.
Struts
Correct Wrong
Shields