Siemens SITRANS LUT400, Руководство по эксплуатации

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A5E33329501 SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS Page 261
mmm
mm
App. A -
Te
c
hni
cal Ref
.
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
Near Range (2.2.4.) programs SITRANS LUT400 to ignore the area in front of the
transducer. 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 (2.12.3.4.) is generally recommended in preference to extending the blanking
distance from factory values.
Far Range
Far Range (2.2.5.) 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 by 30% or 40% can provide stable empty vessel readings.
0
0 0 0
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
0 0 0 0
Distance
Profile
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