Siemens SITRANS LR200 7ML5422, Руководство по эксплуатации

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SITRANS LR200 with mA/HART
112
Operating Instructions, 05/2019, A5E32337676-AE
Position detect (2.8.4.2.)
Description Defines where on the echo the distance measurement is determined. Refer to
"Position detect" under Echo Selection (Page 172) for more detail.
Options Center
Hybrid (center and CLEF)
CLEF (Constrained Leading Edge Fit)
Factory setting Hybrid (center and CLEF)
Related
parameters CLEF range (2.8.4.4.) (Page 112)
Note
If the vessel bottom is being reported as the level instead of the actual material level (at low
level conditions), or if the dielectric constant of the liquid to be monitored is less than 3, set
Position detect to Hybrid and CLEF range (2.8.4.4.) (Page 112) to 0.5 m (1.64 ft).
Echo threshold (2.8.4.3.)
Description Sets the minimum echo confidence that the echo must meet in order to pre-
vent a Loss of Echo condition and the expiration of the LOE timer. When Con-
fidence (2.8.6.1.) (Page 114) exceed Echo Threshold, the echo is accepted as
a valid echo and is evaluated. Use this feature when an incorrect material
level is reported.
Values Range: 0 to 99
Factory default 5
Related
parameter Timer (2.5.2.) (Page 103)
CLEF range (2.8.4.4.)
Description The CLEF algorithm is used mainly to allow correct level reporting for low dK
materials which may otherwise cause an incorrect reading in an empty or
almost empty vessel. It is used from Low Calibration Point (process empty
level) up to the level defined by CLEF range (see illustration below). Above
that point the Center algorithm is used. For more detail, refer to CLEF Range
(Page 175).
Values Range: 0 to 20 m (0 to 65.6 ft)
Parameter reference 0.00 m
Related
parameters
Position detect (2.8.4.2.) (Page 112)