Air Purging; A.2.9 Air Purging - Emerson Rosemount 5408 Reference Manual

A.2.9

Air purging

An air purge connection can prevent clogging of the antenna in extreme applications with
dirt or heavy coating. The easiest way to determine if air purging is needed, is to inspect
the tank internal conditions at the location intended for the transmitter. If there is
normally a thick layer of product build-up there, air purging is most likely needed. Typical
purging media to use is air.
All parabolic antennas come with an integrated air purge connection (see
Figure A-9:
An air purge connection is also available for cone antennas with flanged connection by
selecting option code PC1. This option consists of an antenna with purge holes and a
separate air purge ring (see
Rosemount 5408 and 5408:SIS Level Transmitters
Air Purging for Parabolic Antenna
Figure A-10).
Specifications and Reference Data
Figure A-9).
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