Measurement Range - Siemens SITRANS LR250 Operating Instructions Manual

Auto False Echo Suppression Range must be set to a distance shorter than the distance
to the material level when the environment was learned, to avoid the material echo being
screened out.
Example before Auto False Echo Suppression
default
TVT
Example after Auto False Echo Suppression
false echo

Measurement Range

Near Range (2.5.1.)
Near Range programs SITRANS LR250 to ignore the zone in front of the antenna. The
default blanking distance is 50 mm (1.97") from end of horn antenna.
Near Range allows you to increase the blanking value from its factory default. But Auto
False Echo Suppression (2.5. 1 0.1.) is generally recommended in preference to extending
the blanking distance from factory values.
Far Range (2.5.2.)
Far Range can be used in applications where the base of the vessel is conical or
parabolic. A reliable echo may be available below the vessel empty distance, due to an
indirect reflection path.
Increasing Far Range to 30% or 40% can provide stable empty vessel readings.
7ML19985KL01
material
false
echo
echo
Auto False Echo
learned
Suppression Range
TVT
default
TVT
SITRANS LR250 (FF) – OPERATING INSTRUCTIONS
sensor reference point
Auto False Echo
Suppression
Range set to 2 m
material
echo
echo
marker
High Cal. Pt.
= 0
obstruction
at 1.3 m
material
level at
3.2 m
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