Siemens SITRANS L Operating Instructions Manual page 46

Fault description
Measured value fluctuates
around 10 ... 20 %
Measured value jumps
sporadically to 100 %
during filling
Fault description
Measured value remains
unchanged in the close
range during emptying
Measured value jumps
sporadically towards
100 % during emptying
SITRANS LR100
Operating Instructions, 10/2021, 62705-76-01
Cause
transverse reflection larger than the
level echo
Various echoes from an uneven
medium surface, e.g. a material
cone
Reflections from the medium
surface via the vessel wall
(deflection)
Changing condensation or
contamination on the antenna
Cause
False signal greater than level echo
or level echo too small
Changing condensation or
contamination on the antenna
Diagnostics and troubleshooting
9.5 Treatment of measurement errors
Rectification
Check parameter "Material Type"
and adapt, if necessary
Optimize installation position and
transmitter orientation
Select a more suitable installation
position, optimize transmitter
orientation, e.g. with a swivelling
holder
Carry out a auto false echo
suppression or increase auto
false echo suppression with
condensation/contamination in the
close range by editing
Rectification
Eliminate false signals in the close
range. Check: Antenna must
protrude out of the nozzle
Remove contamination on the
antenna
Minimize interfering installations
in the close range by changing the
polarization direction
After eliminating the false signals,
the auto false echo suppression
must be deleted. Carry out a new
auto false echo suppression
Carry out auto false echo
suppression or increase auto false
echo suppression in the close range
by editing
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