Filter Settings; Advanced Functions In Rrm; Empty Tank Handling; C.3.6 Filter Settings - Emerson Rosemount 5400 Series Reference Manual

Reference Manual
00809-0100-4026, Rev HA
C.3.6

Filter settings

Damping value
The Damping Value parameter determines how quickly the transmitter responds to level
changes and how robust the measurement signal is against noise. A damping value of 10
indicates that in 10 seconds the output from the transmitter is approximately 63 % of the new
level value. Consequently, when there are rapid level changes in the tank, it may be necessary to
decrease the Damping Value for the transmitter to track the surface. In noisy environments,
with low level rates, it may be best to increase the damping value for a stable output signal.
Activate jump filter
The Jump Filter is typically used for turbulent surface applications where it smooths the echo
tracking as the level passes, for example, an agitator. If the surface echo is lost and a new surface
echo is found, the Jump Filter has the transmitter wait before jumping to the new echo so it can
be validated. During that time the new echo has to be considered a valid echo.
C.4

Advanced functions in RRM

C.4.1

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.
2.
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.
Advanced Configuration
Disable the Use Automatic Empty Tank Handling Settings option.
Select the Bottom Echo Visible if Tank is Empty check-box.
Appendix C: Advanced configuration
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