User's Manual

Parameter reference
SITRANS LR250 (FOUNDATION FIELDBUS)
Operating Instructions, 01/2014, A5E32221411-AB
149
Echo Quality (2.5.9.)
Confidence (2.5.9.1.)
Indicates echo reliability: higher values represent better echo quality. The display shows the
echo confidence of the last measurement.
Echo Threshold (2.5.7.3.)
defines the minimum
criterion for echo confidence.
Values
(view only)
0
to
99
Echo Threshold (2.5.7.3.)
Related Parameters
Open the menu
Device – Echo Profile Utilities
and click on the tab
Echo Profile
.
Echo Strength (2.5.9.2.)
Displays the absolute strength (in dB above 1 μV rms) of the echo selected as the measurement
echo.
Values
(view only)
Range:
–20
to
99
TVT (Auto False Echo Suppression) Setup (2.5.10.)
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).