User's Manual

7ML19985KB01 SITRANS LR560 (mA/HART) – INSTRUCTION MANUAL Page 127
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D: Technical Reference
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.
Measurement Range
Near Range (2.7.1.)
Near Range programs SITRANS LR560 to ignore the zone in front of the antenna. The
default blanking distance is 27.8 cm (0.91 ft) from the sensor reference point.
Near Range allows you to increase the blanking value from its factory default. But Shaper
Mode (2.8.4.) is generally recommended in preference to extending the blanking distance
from factory values.
Far Range (2.7.2.)
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.
High Cal. Pt.
= 1 m
obstruction
at 13 m
material
level at
31 m
false
echo
material
echo
default
TVT
sensor reference point
Example before Auto False Echo Suppression
Low Cal.
Pt.
= 45 m
Example after Auto False Echo Suppression
learned
TVT
material
echo
false echo
echo
marker
Auto False Echo
Suppression
Range set to 20 m
Auto False Echo
Suppression Range
default
TVT