Endress+Hauser Micropilot M FMR250, Руководство по эксплуатации

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Installation Micropilot M FMR250 FOUNDATION Fieldbus
16 Hauser
3.3.2 Engineering hints
Orientation
• Recommended distance (1) wall – outer
edge of nozzle: ~1/6 of vessel diameter.
However, the device should not, under any
circumstances, be mounted less than
20 cm (7.87 in) from the vessel wall.
Note!
If the tank wall is not smooth (corrugated
metal, welding seams, irregularities etc.) the
distance from the wall should be kept as large
as possible. If necessary, use a top target
positioner to prevent interference reflections
from the tank wall.
• Not in the centre (3), interference can cause
signal loss.
• Not above the fill stream (4).
• It is recommended to use a weather
protection cover (2) in order to protect the
transmitter from direct sun or rain. Assembly
and disassembly is simply done by means of a
tension clamp (
→
ä
71, "Accessories").
• In extremely dusty applications, the
integrated air purge connection can prevent
clogging of the antenna.
L00-FMR250xx-17-00-00-xx-003
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Vessel installations
• Avoid any installations (1), like limit switches,
struts, etc., inside the signal beam
(
→
ä
17, "Beam angle").
• Symmetrical installations (2), i.e. reinforcing
rings, heating coils, etc., can also interfere
with the measurement.
Optimization options
• Antenna size: the bigger the antenna, the
smaller the beam angle, the less interference
echoes.
• Mapping: the measurement can be optimized
by means of electronic suppression of
interference echoes.
• Antenna alignment: refer to "Optimum
mounting position",
→
ä
20.
• In devices with top target positioner, the
sensor can be optimally aimed within the
vessel and/or interference reflections can be
avoided. The max. angle
β
is ±15°.
• In particular, sensor alignment serves to:
– prevent interference reflections
– extend the maximum possible measuring
range in conical outlets.
• Metallic screens (3) mounted at a slope spread
the radar signals and can, therefore, reduce
interference echoes.
L00-FMR250xx-17-00-00-xx-002
Please contact Hauser for further information.
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