Rosemount 5401, Справочное руководство

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Reference Manual
00809-0100-4026, Rev FA
July 2009
C-7
Rosemount 5400 Series
ADVANCED FUNCTIONS
IN RRM
Empty Tank Handling
Bottom Echo Visible
The
Bottom Echo Visible...
parameter allows the transmitter to separate the
product surface from the tank bottom by identifying the bottom echo as a
disturbance echo. This is useful for products relatively transparent for
microwaves, such as oil. For non-transparent products, such as water, there
is no visible bottom echo until the tank is empty.
To enable this function:
1. Disable the
Use Automatic Empty Tank Handling Settings
option.
2. Select the
Bottom Echo Visible if Tank is Empty
check box.
Only use this function for tanks with a Flat bottom type where the radar echo
from the tank bottom is clearly visible. If there is no distinct bottom echo, even
if the tank is empty, this parameter should be disabled. Otherwise, if the
surface echo is temporarily lost, the transmitter starts searching for the
product surface in the tank and may incorrectly interpret any object as the
surface.
The spectrum function in the RRM program can be used to check if the gauge
detects the tank bottom in an empty tank.
Amplitude
Dist
ance
Echo from
tank bottom
Surface echo