NivoRadar
®
Continuous level measurement
Series NR 4000
Technical information / Instruction manual
Diagnostics and servicing
page 41
Fault description
Cause
Rectification
Measured value jumps to
≥ 100 % or 0 m distance
Leve
l
time
0
Level echo is no longer detected in
the close range due to foam genera-
tion or false signals in the close range.
The sensor goes into overfill protection
mode. The max. level (0 m distance)
as well as the status message "
Overfill protection" are output.
Check measuring point: Antenna
should protrude out of the threaded
mounting socket, possible false ech-
oes through flange socket?
Remove contamination on the antenna
Liquids: Measurement error during emptying
Fault description
Cause
Rectification
Measured value remains un-
changed in the close range
during emptying
Level
time
0
False signal larger than the level echo
Level echo too small
Check measuring point: Antenna
should protrude out of the threaded
mounting socket, possible false ech-
oes through flange socket?
Remove contamination on the antenna
In case of interferences due to instal-
lations in the close range: Change
polarisation direction
After eliminating the false signals, the
false signal suppression must be de-
leted. Carry out a new false signal
suppression
Measured value jumps spo-
radically towards 100 %
during emptying
Level
time
0
Varying condensation or contamination
on the antenna
Carry out false signal suppression or
increase false signal suppression in the
close range by editing
With bulk solids, use radar sensor with
purging air connection
Bulk solids: Measurement error at constant level
Fault description
Cause
Rectification
Measured value shows a too
low or too high level
Leve
l
time
0
Min./max. adjustment not correct
Adapt min./max. adjustment
Incorrect linearization curve
Adapt linearization curve
Measured value jumps to-
wards 100 %
Level
time
0
Due to the process, the amplitude of
the product echo decreases
A false signal suppression was not car-
ried out
Carry out a false signal suppression
Amplitude or position of a false signal
has changed (e.g. condensation, build-
up); false signal suppression no longer
matches actual conditions
Determine the reason for the changed
false signals, carry out false signal
suppression, e.g. with condensation.
