Siemens SITRANS L Operating Instructions Manual page 44

Fault description
Measured value jumps
towards 0 % during filling
Measured value jumps
towards 100 % during
filling
Measured value jumps
sporadically to 100 %
during filling
Measured value jumps to
≥ 100 % or 0 m distance
Fault description
Measured value remains
unchanged in the close
range during emptying
SITRANS LR100
Operating Instructions, 10/2021, 62705-76-01
Cause
The level echo cannot be
distinguished from the false signal
at a false signal position (jumps to
multiple echo)
Due to strong turbulence and
foam generation during filling, the
amplitude of the level echo sinks.
Measured value jumps to false
signal
Varying condensation or
contamination on the antenna
Level echo is no longer detected
in the close range due to foam
generation or false signals in the
close range. The transmitter goes
into overfill protection mode. The
max. level (0 m distance) as well
as the status message ""Overfill
protection" are output.
Cause
False signal larger than the level
echo
Level echo too small
Diagnostics and troubleshooting
9.5 Treatment of measurement errors
Rectification
Create a new auto false echo
suppression
Adapt max. adjustment
In case of interferences due to
installations in the close range:
Change polarisation direction
Chose a more suitable installation
position
Carry out a auto false echo
suppression
Carry out a auto false echo
suppression or increase auto
false echo suppression with
condensation/contamination in the
close range by editing
Check measuring point: Antenna
should protrude out of the threaded
mounting nozzle, possible false
echoes through flange nozzle?
Remove contamination on the
antenna
Rectification
Check measuring point: Antenna
should protrude out of the threaded
mounting nozzle, possible false
echoes through flange nozzle?
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