VEGA VEGAPULS 61 (≥ 2.0.0 - ≥ 4.0.0) Foundation Fieldbus Approval according to LPR radio standard - Manual (Page 59)

The images in column "Error pattern" show the actual level with a
broken line and the level displayed by the sensor as a continuous line.
1
2
L
e
ve
l
time 0
1 Real level
2 Level displayed by the sensor
Instructions:
l Wherever the sensor displays a constant value, the reason could
also be the fault setting of the current output to "Hold value"
l In case of a too low level indication, the reason could be a line
resistance that is too high
Measurement error with constant level
Fault description Error pattern Cause Rectification
1. Measured value
shows a too low or too
high level
Level
time 0
l Min./max. adjustment not cor-
rect
l Adapt min./max. adjustment
l Linearization curve incorrect l Adapt linearization curve
l Installation in a bypass tube or
standpipe, hence running time
error (small measurement er-
ror close to 100 %/large error
close to 0 %)
l Check parameter "Application"
with respect to vessel form,
adapt if necessary (bypass,
standpipe, diameter)
2. Measured value
jumps towards 0 %
Level
time 0
l Multiple echo (vessel top, pro-
duct surface) with amplitude
higher than the level echo
l Check parameter "Application",
in particular Vessel top, Pro-
duct type, Dished bottom, High
dielectric value and adapt if
necessary
3. Measured value
jumps towards 100 %
Level
time 0
l Due to the process, the amp-
litude of the product echo sinks
l A false signal suppression was
not carried out
l Carry out false signal suppres-
sion
l Amplitude or position of a false
echo has changed (e.g. con-
densation, buildup); false sig-
nal suppression no longer
matches
l Determine the reason for the
changed false echoes, carry
out false signal suppression, e.
g. with condensation
VEGAPULS 61 • Approval according to LPR radio standard 59
9 Diagnosis, Asset Management and service
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