Operating Instructions

Table Of Contents
Specifies the range within which Learned TVT is used [see Auto False Echo Suppression
(2.8.7.1.) for more detail].
Values Range: 0.00 to 20.00 m
Default: 1.00 m
Related parameters Units (2.2.1.)
1. Calculate range according to Auto False Echo Suppression (2.8.7.1.) steps 1 and 2.
2. Press RIGHT arrow to open Edit mode.
3. Enter the new value and press RIGHT arrow to accept it.
4. Set Auto False Echo Suppression (2.8.7.1.).
Hover Level (2.8.7.3.)
Note
Changes take effect only at the next measurement.
Defines how high the TVT (Time Varying Threshold) is placed above the noise floor of the echo
profile, as a percentage of the difference between the peak of the largest echo in the profile and
the noise floor. See Auto False Echo Suppression (2.8.7.1.) for an illustration.
Values Range: 0 to 100%
Default: 40%
When the device is located in the center of the vessel, the TVT hover level may be lowered to
increase the confidence level of the largest echo.
Shaper Mode (2.8.7.4.)
Enables/disables the TVT shaper.
Options ON
* OFF
TVT shaper (2.8.8.)
Note
The range is –100 to 100 bits. With 2 bits per dB this gives a range of –50 to 50 dB.
Shaper Mode (2.8.7.4.) must be turned ON in order for TVT shaper points to be transferred.
Adjusts the TVT (Time Varying Threshold) at a specified range (breakpoint on the TVT). This
allows you to reshape the TVT to avoid unwanted echoes. There are 40 breakpoints arranged
in 5 groups. (We recommend using SIMATIC PDM to access this feature.)
Parameter reference
SITRANS LR250 with mA/HART
128 Operating Instructions, 10/2019, A5E32220602-AG