Rockwell Automation 1734sc-IE4CH E+H Instruments via HART to PlantPAx User Manual - Manual (Page 110)

110 Rockwell Automation Publication PROCES-UM002A-EN-P - July 2014
Appendix F Levelflex M Guided Radar Level
Levelflex provides continuous level measurement of powdery to granular bulk
solids, e.g. plastic granulate, and liquids. In addition, the Smart Transmitter offers
continuous measurement of interfaces between two liquids with very different
dielectric constants, such as in the case of oil and water, for example.
• Measurement independent of density or bulk weight, conductivity,
dielectric constant, temperature and dust, e.g. during pneumatic filling.
• Measurement is also possible in the event of foam or if the surface is very
turbulent.
• Measurement independent of density, conductivity and temperature.
• Electronics version for the simultaneous measurement of the level of
interfaces and the total level in liquids.
• Special version for the measurement of the level of interfaces at a constant
total level.
The dielectric constant (DK) of the medium has a direct impact on the degree of
reflection of the high frequency pulses. In the case of large DK values, such as for
water or ammonia, there is strong pulse reflection, while with low DK values,
such as for hydrocarbons, weak pulse reflection is experienced.
Item Description
E Empty distance
F Span (full distance)
D Distance from sensor membrane - product surface
L Level
20 mA
100%
4 mA
0%
D
probe length LN
L
F
E
flange:
reference point of
measurement