Siemens SITRANS LUT400 Operating Instructions Manual page 193

To set Auto False Echo Suppression via the local push buttons:
Options
c)
d)
e)
2.12.3.2. Auto False Echo Suppression Range
Specifies the range within which Learned TVT is used (see Auto False Echo
Suppression on page 184 for more detail).
Values
a)
b)
c)
d)
2.12.3.3. Hover Level
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 Example
before Auto False Echo Suppression on page 261 for an illustration.
Values
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.
2.12.3.4. Shaper Mode
Enables/disables the TVT shaper.
Options
Turn TVT Shaper Mode ON before using
Shaper ON and OFF while monitoring the effect to pick up the true echo.
2.12.4. TVT Shaper
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.)
A5E33329501 SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS
OFF Default TVT will be used.
* ON 'Learned' TVT will be used.
LEARN 'Learn' the TVT.
Navigate to Setup (2.) > Signal Processing (2.12.) > TVT Setup (2. 1 2.3.)
> Auto False Echo Suppression Range (2.12.3.2.), and enter the value
calculated in step b).
Navigate to Setup (2.) > Signal Processing (2.12.) > TVT Setup (2. 1 2.3.)
> Auto False Echo Suppression (2.12.3.1.), and press RIGHT arrow to
open Edit Mode
Select Learn. The device will automatically revert to On (Use
Learned TVT) after a few seconds.
Calculate range according to Auto False Echo Suppression (2.12.3.1.)
steps a) and b).
Press RIGHT arrow to open Edit mode.
Enter the new value and press RIGHT arrow to accept it.
Navigate to Setup (2.) > Signal Processing (2.12.) > TVT Setup (2. 1 2.3.)
> Auto False Echo Suppression (2.12.3.1.), and set value.
Range: 0.000 to 60.000 m
Default: 1.000
Range: 0 to 100
Default: 40
ON
* OFF
2. 1 2.4.TVT Shaper
. Turn the TVT
Page 185