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4 false echoes, Shoulders, Vessel installations – VEGA VEGAPULS 51V…54V User Manual

Page 36: Struts

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36

VEGAPULS 51 V … 54 V

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Mounting and installation - False echoes

4.4 False echoes

The installation place of the radar sensor
must be selected such that no struts or
inflowing material cross the radar signals.
The following examples show frequent meas.
problems and how they can be avoided.

Shoulders

Vessel forms with flat shoulders pointing to
the antenna can influence the measurement
due to their hard false echoes. Deflectors
above these flat shoulders diffuse the false
echoes and ensure a reliable measurement.

Inlets, e.g. for material mixing with flat surface
pointing to the radar sensor, should be
covered by a screen. False echoes are
hence gated out.

Flat shoulders

Shoulders (inlets)

Vessel installations

Struts, such as e.g. a ladder often cause
false echoes. Note when planning a
measurement loop that the radar signals
reach the measured products without
problems.

Struts

Struts such as vessel installations can cause
strong false echoes which can overlay the
useful echo. Small shields avoid a direct false
echo reflection. The false echoes are diffused
and filtered out by the meas. electronics as
"echo noise".

Vessel installations

Struts

Correct

Wrong

Correct

Wrong

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Correct

Wrong

Correct

Wrong

Ladder

Ladder

Shields