Measurement Range; Measurement Response; A.3.7 Measurement Range - Siemens SITRANS LR560 Operating Instructions Manual

Technical reference
A.3 Echo processing
A.3.7

Measurement range

NEAR RANGE (2.7.1.) (Page 121)
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) (Page 127) is generally recommended in preference to extending the blanking
distance from factory values.
FAR RANGE (2.7.2.) (Page 121)
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.
A.3.8

Measurement response

Note
Units are defined in Quick Start Wizard (1.1.) and are in meters by default.
RESPONSE RATE (2.4.1.) (Page 114) limits the maximum rate at which the display and output
respond to changes in the measurement. There are three preset options: slow, medium, and
fast.
Once the real process fill/empty rate (m/s by default) is established, a response rate can be
selected that is slightly higher than the application rate. Response Rate automatically adjusts the
filters that affect the output response rate.
RESPONSE RATE (2.4.1.)
(Page 114)
Factory
setting:
186
FILL RATE/MIN (2.4.2.) (Page 115)/EMPTY
RATE/MIN (2.4.3.) (Page 115)
Slow 0.1 m/min (0.32 ft/min)
Medium 1.0 m/min (3.28 ft.min)
Fast 10.0 m/min (32.8 ft/min)
DAMPING FILTER
(2.2.3.) (Page 112)
SITRANS LR560 (mA/HART)
Operating Instructions, 06/2017, A5E34647946-AD
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