Diagnostics and troubleshooting
12.5 Treatment of measurement errors
Fault description
Cause
Rectification
Due to the process, the amplitude
of the product echo decreases
A auto false echo suppression was
not carried out
Carry out a auto false echo
suppression
Measured value jumps
towards 100 %
Amplitude or position of a
false signal has changed (e.g.
condensation, buildup); auto
false echo suppression no longer
matches actual conditions
Determine the reason for the
changed false signals, carry out
auto false echo suppression, e.g.
with condensation.
Fault description
Cause
Rectification
The level echo cannot be
distinguished from the false signal
at a false signal position (jumps to
multiple echo)
Remove/reduce false signal:
minimize interfering installations by
changing the polarization direction
Chose a more suitable installation
position
Measured value jumps
towards 0 % during filling
Transverse reflection from an
extraction funnel, amplitude of the
transverse reflection larger than the
level echo
Direct transmitter to the opposite
funnel wall, avoid crossing with the
filling stream
Various echoes from an uneven
medium surface, e.g. a material
cone
Check parameter "Material Type"
and adapt, if necessary
Optimize installation position and
transmitter orientation
Measured value fluctuates
around 10 … 20 %
Reflections from the medium
surface via the vessel wall
(deflection)
Select a more suitable installation
position, optimize transmitter
orientation, e.g. with a swivelling
holder
Measured value jumps
sporadically to 100 %
during filling
Changing condensation or
contamination on the antenna
Carry out a auto false echo
suppression or increase auto
false echo suppression with
condensation/contamination in the
close range by editing
SITRANS LR150
Operating Instructions, 08/2020,
A5E50352155
83