Siemens SITRANS L Operating Instructions Manual page 66

Signal quality
Echo quality:
Displays the echo quality. The higher the value, the higher the echo quality.
Echo signal strength:
Displays the strength of the valid echo in dB.
Noise average value:
Displays the average value of the noise in dB.
Setting
SIGNAL
Echo configuration
Near range:
Sets minimum distance from transmitter reference point, beyond which an echo
should be considered valid. This is sometimes referred to as blanking or a blocking
distance. When the begin of the measuring range is activated, the mm value is edited
by pressing the " ↓ key.
Setting
SIGNAL
TVT configuration
Defines the threshold curve below which all echoes are ignored.
The Hover Level sets the offset of the TVT (Time varying threshold) curve with
respect to the basic noise of the echo profile. Specified in dB with respect to the basic
noise and peak value of the largest echo.
Automatic false echo suppression (AFES) is used for false echo suppression in vessels
with known installations. When AFES is activated, the effective range is selected as
distance in mm by pushing the button " ↓.
A determined TVT curve replaces the preset TVT curve in the set effective range.
Procedure for optimum results with auto false echo suppression:
1.
SITRANS LR150
Operating Instructions, 10/2022, 62711-76-01, A5E50352155
Selection
SIG QUALITY
Selection
ECHO CONFIG
If possible, set the automatic false echo suppression during commissioning by
executing the " Auto false echo suppression wizard".
Setup with the integrated HMI
Selection
CONFIDENCE
ECHO SIG STR
NOISE AVG
Selection
NEAR RANGE ON
NEAR RANGE OFF
7.8.1 Signal
Description
Echo quality
Echo signal strength
Noise average value
Description
Measuring range begin
activated
Measuring range begin value
Measuring range begin
deactivated
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