Operating Instructions

Table Of Contents
4.3.1 Nozzle design
Threaded PVDF antenna Stainless steel horn antenna
Polymeric lens versions Hygienic encapsulated antenna (HEA)
Minimum clearance: 10 mm (0.4")
Minimum diameter: 50 mm (2")
Maximum nozzle length
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
1)
.
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.
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.
The maximum nozzle length for the polymeric lens versions is 500 mm (19.68").
1)
Not applicable for polymeric lens versions or HEA
4.3.2 Nozzle location
Avoid central locations on tall, narrow vessels
Nozzle must be vertical and clear of imperfections
Installing/mounting
4.3 Proper mounting
SITRANS LR250 with mA/HART
26 Operating Instructions, 10/2019, A5E32220602-AG