Siemens Sitrans LR200 Instruction Manual page 98

2.8.7. TVT setup
Note: Default settings in the parameter tables are indicated with an asterisk
(*) unless explicitly stated.
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 (2.8.7.1.) on page 126 for a more detailed
explanation.
Notes:
• Make sure material level is below all known obstructions when Auto
• Note the distance to material level when Auto False Echo learns the
• Set Auto False Echo Suppression and Auto False Echo Suppression
• If the vessel contains an agitator it should be running.
• Before adjusting these parameters, rotate the instrument for best sig-
Before Auto False Echo Suppression
a)
b)
Page 90 SITRANS LR200 (HART) – INSTRUCTION MANUAL
Auto False Echo Suppression
False Echo Suppression is used to learn the echo profile. (An empty or
almost empty vessel is recommended.)
environment. Set Auto False Echo Suppression Range to a shorter
distance to avoid the material echo being screened out.
Range during startup, if possible.
nal (lower false-echo amplitude).
TVT
Hover
Level
Determine Auto False Echo Suppression Range. Measure the actual
distance from the sensor reference point to the material surface
using a rope or tape measure.
Subtract 0.5 m (20") from this distance, and use the resulting value.
default TVT
false echo
material level
echo marker
7ML19985JP02