Nozzle Design - Siemens SITRANS LR250 Operating Instructions Manual

4.3.1

Nozzle design

Threaded PVDF antenna
Flanged encapsulated antenna (FEA)
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②
③
④
● 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)
Operating Instructions, 08/2014, A5E32221411-AC
Minimum clearance: 10 mm (0.4")
Minimum diameter: 50 mm (2")
Maximum nozzle length
Maximum length/diameter ratio 1:1
Stainless steel horn antenna
Hygienic encapsulated antenna (HEA)
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1)
Installing/mounting
4.3 Proper mounting
27