Vega VEGAPULS 68 - Page 68

68
9 Diagnosis, asset management and service
VEGAPULS 68 • Foundation Fieldbus
36538-EN-170405
1
2
Level
time
0
1 Real level
2 Level displayed by the sensor
Notes:
•
Whenever the sensor displays a constant value, the reason could
also be that the fault setting of the current output is set to "Hold
value"
•
If the level indication is too low, the reason could be a line resist-
ance that is too high
Measurement error with constant level
Fault description Error pattern Reason Rectication
1. Measured value
shows a too low or too
high level
Level
time
0
•
Min./max. adjustment not
correct
•
Adapt min./max. adjustment
•
Incorrect linearisation curve
•
Adapt linearisation curve
2. Measured value
jumps towards 100 %
Level
time
0
•
Due to the process, the
amplitude of the product echo
decreases
•
A false signal suppression was
not carried out
•
Carry out a false signal suppres-
sion
•
Amplitude or position of a false
signal has changed (e.g. con-
densation, buildup); 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