Siemens 7ML5431 - Page 132

Parameter reference
SITRANS LR250 with mA/HART
132 Operating Instructions, 10/2019, A5E32220602-AG
TVT Setup (2.8.7.)
Note
Default settings in the parameter tables are indicated with an
asterisk (*) unless explicitly
stated.
Auto False Echo Suppression (2.8.7.1.)
Used together with Auto False Echo Suppression Range (2.8.7.2.) to screen out false
echoes in a vessel with known obstructions. A ’learned TVT’ (time varying threshold)
replaces the default TVT over a specified range. See
Auto False Echo Suppression
(Page 238
) for a more detailed explanation.
Note
•
Make sure material level is below all known obstructions when Auto False Echo
Suppression is used to learn the echo profile. (An empty or almost empty vessel is
recommended.)
•
Note the distance to material level when Auto False Echo learns the environment. Set
Auto False Echo Suppression Range to a shorter distance to avoid the material echo
being screened out.
•
Set Auto False Echo Suppression and Auto False Echo Suppression Range during
startup, if possible.
•
If the vessel contains an agitator it should be running.
•
Before adjusting these parameters, rotate the instrument for best signal (lower false-
echo
amplitude).