KROHNE OPTIWAVE 7300 C Handbook page 51

51
Function (Fct.)
C.1.10.0 Reference offset
C.1.11.0 Tank bottom offset
C.1.12.0 Time constant
C.1.13.0 Measuring mode
C.1.14.0 Product Er
C.1.15.0 Tracing velocity
C.1.16.0 Multiple reflections
C.1.17.0 Empty spectrum
On/Off
C.1.19.0 Units for tables
Input Range
-50 m or -164 ft to 50 m
or 164 ft. 0 m or 0 ft
-50 m or -164 ft to 50 m
or 164 ft. 0 m or 0 ft
0 to 100 seconds. 10 sec
Direct measuring, tank
bottom following (TBF)
partial, tank bottom
following (TBF) full. Direct
measuring
1.01 to 10. 1
0.001 m/min to 10 m/min.
0.5 m/min
Yes or no. No
On or off. On
OPTIWAVE 7300 C
Handbook OPTIWAVE 7300 C
Description
Offset relating to a reference location
(distance). This value is positive when the
reference location is above the device
flange face and negative if below.
Offset relating to a reference location
(level). The device reference point for this
parameter is the bottom of the tank,
related to Tank height (C.1.2.0). This
value is positive when the reference
location is below the tank bottom and
negative if above.
Using this function, the device processes
several measurement readings to filter out
disturbances. Increasing the time constant
will smoothen the integrated readings,
decreasing will roughen the readings.
The device tracks level using different
methods. Direct measuring is
recommended where Er => x.xx,
depending on tank type. For products with
Er < x.xx, TBF mode is required. Partial
TBF mode is mainly used for storage
tanks with flat bottoms. Full TBF mode is
mainly used for process tanks.
Accessible when a TBF measurement
mode is selected in menu item C.1.13.0. A
major parameter for RADAR level
measurement devices. Manually sets the
Er value of the product.
Defines the maximum rate of change of
level that can occur. The measured value
cannot change at a faster rate than the
tracing velocity.
Common in storage tanks with an
extremely calm surface, typically when the
device is mounted on a large nozzle
(manhole) or centred on a dome roof.
Multiple reflections also occur when the
tank has a flat or only slighty convex roof.
Such multiple reflections tend to result in
lower-than-actual level readings. In such
cases, activate this function.
An empty spectrum is used to surpress
interference signals produced by fixed and
moving obstacles inside the tank. For this
function an empty spectrum needs to be
recorded first. This is done in the Quick
setup menu under Empty spectrum
(A.1.3.0).
The device can perform volume and
mass conversion operations by pairing
values in a table. The units for the table
columns can be picked from the lists
here.