Rosemount 5401, Справочное руководство

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Reference Manual
00809-0100-4026, Rev FA
July 2009
3-9
Rosemount 5400 Series
Install the transmitter as follows:
• Align the antenna vertically
• Choose the largest antenna diameter possible. A larger receiving area
concentrates the radar beam and ensures maximum antenna gain.
Increased antenna gain permits greater margin for weak surface
echoes. A larger antenna also results in smaller beam angle and
thereby, less interference from any internal structures in the tank
• For best measurement performance, the antenna should extend below
the nozzle 0.4 in. (10 mm) or more
For more information, see “Nozzle Considerations” on page 3-5.
Service Space
For easy access to the transmitter, mount it with sufficient service space.
There is no requirement on clearance distance from the tank wall, provided it
is flat and free of obstructions such as heating coils and ladders. The optimal
location is often 1/4 of the tank diameter.
Figure 3-10. Service space
recommendations.
A
B
C
Rod Antenna Cone Antenna
A
B
C
C
B
A
Process Seal Antenna
Service space Distance inch (mm)
A
Cone, Rod, Process Seal 20 (500)
B
Cone, Rod 24 (600)
Process Seal 33 (850)
Inclination Maximum angle
C
Cone, Rod, Process Seal 3°