Emerson Rosemount 5900C, Reference Manual

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2.5.3 Array antenna
The Rosemount 5900C with Still-pipe Array Antenna is used on tanks with still pipes and
with all products suited for still pipes, except Methanol, for which the other antennas are
better suited.
The gauge uses a low-loss radar propagation mode which virtually eliminates the influence
of the still pipe condition. Measurement is made with highest accuracy even when the
pipe is old, rusty and covered with deposits.
The Still-pipe Array Antenna fits 5, 6, 8, 10, and 12 inch pipes. It can be mounted on an
existing still pipe and there is no need to take the tank out of operation during installation.
There are two versions of the Rosemount 5900C with Still-pipe Array Antenna: fixed and
hinged hatch. The hinged hatch enables full pipe size product sampling or verification
hand-dips.
Figure 2-9: Array Antenna
2.5.4 LPG/LNG Antenna
The Rosemount 5900C with LPG/LNG Antenna is designed for level measurements in LPG
and LNG tanks. A 4 inch still-pipe is used as a wave guide for the measurement and
prevents a turbulent surface from disturbing the measurement. Radar signals are
transmitted inside the pipe towards the surface.
The pressure sealing is a PTFE window with drip-off design. It is approved for use in
pressure vessels. As standard the gauge is equipped with a fire-proof block valve. An
optional vapor space pressure sensor is also available.
The Rosemount 5900C with LPG/LNG Antenna is available in two versions for 150 PSI and
300 PSI.
The Verification Pin allows you to verify measurements without opening the tank by
comparing the measured distance with the actual distance to the Verification Pin.
Reference Manual Overview
00809-0100-5901 September 2019
Rosemount 5900C Radar Level Gauge 25