Siemens SITRANS L Series Operating Instructions Manual page 46

Measured value fluctuates
around 10 ... 20 %
Measured value jumps sporadi-
cally to 100 % during filling
Measured value remains un-
changed in the close range dur-
ing emptying
Measured value jumps sporadi-
cally towards 100 % during emp-
tying
Measured value fluctuates
around 10 ... 20 %
SITRANS LR110
Operating Instructions, 01/2020, A5E49829006
Fault description
Fault description
11.5 Treatment of measurement errors
Cause
Transverse reflection from an ex-
traction funnel, amplitude of the
transverse reflection larger than
the level echo
Various echoes from an uneven
product surface, e.g. a material
cone
Reflections from the product sur-
face via the vessel wall (deflec-
tion)
Changing condensation or cont-
amination on the antenna
Cause
False signal greater than level
echo or level echo too small
Changing condensation or cont-
amination on the antenna
Various echoes from an uneven
product surface, e.g. an extrac-
tion funnel
Diagnostics and troubleshooting
Rectification
Direct transmitter to the oppo-
site funnel wall, avoid crossing
with the filling stream
Check parameter "Material Type"
and adapt, if necessary
Optimize installation position
and transmitter orientation
Select a more suitable installa-
tion position, optimize transmit-
ter orientation, e.g. with a swiv-
elling holder
Carry out a auto false each sup-
pression or increase auto false
each suppression with conden-
sation/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 sig-
nals, the auto false each sup-
pression must be deleted. Carry
out a new auto false each sup-
pression
Carry out auto false each sup-
pression or increase auto false
each suppression in the close
range by editing
Check parameter "Material Type"
and adapt, if necessary
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