Siemens SITRANS LR250 Kompaktbetriebsanleitung Seite 13

4.3.2 Nozzle design
Threaded PVDF antenna
Flanged encapsulated antenna (FEA)
①
Minimum clearance: 10 mm (0.4")
②
Minimum diameter: 50 mm (2")
③
Maximum nozzle length
④
Maximum length/diameter ratio 1:1
● The end of the antenna must protrude a minimum of 10 mm (0.4") to avoid false echoes being reflected from the nozzle
● Minimum recommended nozzle diameter for the threaded PVDF antenna is 50 mm (2").
● An antenna extension (100 mm/3.93") is available for the horn antenna only.
● The maximum nozzle length for the FEA is 500 mm (19.68") when the nozzle diameter is DN150 (6"). Only shorter lengths
are recommended for smaller diameters.
● When installing the SITRANS LR250 with hygienic process connection, it is good hygienic practice to install the antenna in a
nozzle that has a maximum length/diameter ratio of 1:1. For example, 2" (DN50) diameter nozzle should be no longer than 2"
(50 mm).
● When removing any sanitary/hygienic clamp version of the HEA to clean the lens, ensure it is re-installed in the exact
position it was removed from, to avoid re-commissioning the device.
Not applicable for FEA or HEA
1)
SITRANS LR250 (FOUNDATION FIELDBUS)
A5E33472700-AA, 08/2014
Stainless steel horn antenna
Hygienic encapsulated antenna (HEA)
.
1)
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