Siemens SITRANS LR250 Schnellstartanleitung Seite 10

Nozzle location
• Avoid central locations on tall, narrow vessels,
which can generate false echoes.
• Nozzle must be vertical.
Environment
• Provide an environment suitable to the housing
rating and materials of construction.
• Provide a sunshield if the device will be mounted
in direct sunlight.
Beam angle
• Beam angle is the width of the cone where the energy density is half of the peak energy
density.
• The peak energy density is directly in front of and in line with the antenna.
• There is a signal transmitted outside the beam angle, therefore false targets may be
detected.
Horn
antenna
emission
cone
beam
angle
beam angle:
size beam angle
1.5" = 19°
2" = 15°
3" = 10°
4" = 8°
Emission Cone
• Keep emission cone free of interference from ladders, pipes, I-beams or filling streams.
Access for programming
• Provide easy access for viewing the display and programming via the handheld program-
mer.
Page EN-8 SITRANS LR250 (HART) – QUICK START MANUAL
Flanged encapsulated
antenna (FEA)
emission
cone
beam
angle
beam angle:
size beam angle
2"/DN50/50A = 12.8°
3"/DN80/80A = 9.6°
4"/DN100/100A = 9.6°
6"/DN150/150A = 9.6°
preferred
undesirable
Threaded PVDF
antenna
emission
cone
beam
angle
beam angle = 19°
A5E31997170