Siemens SITRANS LR200 7ML5422, Руководство по эксплуатации

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SITRANS LR200 with mA/HART
Operating Instructions, 05/2019, A5E32337676-AE
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7.2.7.2 Far range (2.8.2.)
Description Allows the material level to drop below Low Calibration Point without generating
a Loss of Echo (LOE) state. Use this feature if the measured surface can drop
below the Low Cal. Point in normal operation. For an illustration, refer to Sensor
mode (2.2.2.) (Page 99).
Values 0 to 23 m (75.4 ft). Min. value depends on the setting for Low calibration point
(2.3.1.) (Page 100).
Factory setting Low calibration point (2.3.1.) (Page 100) s 1 m (3.2 ft)
Note
Far Range can extend beyond the bottom of the vessel.
7.2.7.3 Propagation factor (2.8.3.)
Propagation Factory compensates for the change in microwave velocity due to propagation
within a metal stillpipe instead of in free space.
Note
When operating with a waveguide antenna or stillpipe, values for CLEF range (2.8.4.4.)
(Page 112) and for the propagation factor should be set according to the antenna frequency
and the antenna/pipe size (see the tables below). For reliable results the horn size must be
close to the pipe size
6.3 GHz Model
Values Range: 0.3 to 1.5 depending on pipe size.
Factory setting 1.000
Antenna/Pipe
Size (I.D.)
1)
50 mm (2”) 80 mm (3”) 100 mm (4”) 150 mm (6”) 200 mm (8”)
Propagation
Factor
0.8298 0.9372 0.9603 0.9825 0.9902
1)
Since pipe dimensions may vary slightly, the propagation factor may also vary.
7.2.7.4 Echo select (2.8.4.)
Algorithm (2.8.4.1.)
Description Selects the algorithm to be applied to the echo profile to extract the true echo.
Options tF (factory setting) true First echo
L Largest echo
BLF Best of First or Largest echo