Operating Conditions: Installation With Level Measurement; General Information On Level Measurement - Endress+Hauser Levelflex M FMP40 Technical Information

General information on level
measurement
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Operating conditions: installation with level measurement

Probe selection (→ ä 6)
• Normally, rope probes should be used for bulk solids, rod probes are only suitable for short measuring ranges
up to approx. 2 m in bulk solids. This applies above all to applications in which the probe is installed laterally
at an angle and for light and pourable bulk solids.
• Normally use rod or coax probes for liquids. Rope probes are used in liquids for measuring ranges > 4 m and
with restricted ceiling clearance which does not allow the installation of rigid probes.
• Coax probes are suited to liquids with viscosities of up to approx. 500 cst. Coax probes can measure most
liquefied gases, as of a dielectric constant of 1.4. Moreover, installation conditions, such as nozzles, tank
internal fittings etc., have no effect on the measurement when a coax probe is used. A coax probe offers
maximum EMC safety when used in plastic tanks.
• In the case of large silos, the lateral pressure on the rope can be so high that a rope with plastic jacketing
must be used. We recommend PA-coated ropes be used for cereal products wheat, flour etc.
Mounting location
• Do not mount rod or rope probes in the filling curtain (2).
• Mount rod and rope probes away from the wall (B) at such
a distance that, in the event of buildup on the wall, there
is still a minimum distance of 100 mm between the probe
and the buildup.
• Mount rod and rope probes as far away as possible from
installed fittings. "Mapping " must be carried out during
commissioning in the event of distances < 300 mm.
• When installing rod and rope probes in plastic containers,
the minimum distance of 300 mm also applies to metallic
parts outside the container.
• Rod and rope probes may not, at times, contact metallic
container walls or floors.
• Minimum distance of probe end to the container floor (C):
– Rope probe: 150 mm
– Rod probe: 50 mm
– Coax probe: 10 mm
• When installing outdoors, it is recommended that you use
a protective cover (1) (→ ä 62, "Accessories").
• Avoid buckling the rope probe during installation or
operation (e.g. through product movement against silo
wall) by selecting a suitable mounting location.
Levelflex M FMP40
1
B
C
L00-FMP4xxxx-17-00-00-xx-003
Endress+Hauser
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