Vega VEGAPULS 61 Operating Instructions Manual page 65

Fault description
6. Measured value re-
mains momentarily
unchanged during fill-
ing and then jumps to
the correct level
7. Measured value
jumps towards 0 %
during filling
8. Measured value
jumps towards 100 %
during filling
9. Measured value
jumps sporadically to
100 % during filling
10. Measured value
jumps to ≥ 100 % or
0 m distance
Measurement error during emptying
Fault description
11. Measured value re-
mains unchanged in
the close range during
emptying
VEGAPULS 61 • Foundation Fieldbus
Error pattern Cause
– Turbulence on the product
surface, quick filling
0 time
– Amplitude of a multiple echo
(vessel top - product surface) is
larger than the level echo
0
time
– The level echo cannot be distin-
guished 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
0 time
– Varying condensation or con-
tamination on the antenna
0 time
– Level echo is no longer
detected in the close range
due to foam generation or false
signals in the close range. The
sensor goes into overfill protec-
0
time
tion mode. The max. level (0 m
distance) as well as the status
message "Overfill protection"
are outputted.
Error pattern Cause
– False signal larger than the
level echo
– Level echo too small
0
time
9 Diagnosis, asset management and service
Rectification
– Check parameters, change if
necessary, e.g. in dosing ves-
sel, reactor
– Check parameter "Application",
especially vessel top, type of
medium, dished bottom, high
dielectric constant, and adapt if
necessary
– In case of interferences due to
installations in the close range:
Change polarisation direction
– Chose a more suitable installa-
tion position
– Carry out a false signal sup-
pression
– Carry out a false signal sup-
pression or increase false
signal suppression with con-
densation/contamination in the
close range by editing
– Check measuring site: Antenna
must protrude out of the socket
– Remove contamination on the
antenna
– Use a sensor with a more suit-
able antenna
Rectification
– Eliminate false signal in the
close range. Check: Antenna
must protrude from the socket
– Remove contamination on the
antenna
– In case of interferences due to
installations in the close range:
Change polarisation direction
– After eliminating the false sig-
nals, the false signal suppres-
sion must be deleted. Carry out
a new false signal suppression
65