Siemens SITRANS LG270 Operating Instructions Manual page 62

Measurement error during filling
Fault description
Measured value remains in
the area of the bottom dur-
ing filling
0
time
Measured value remains
momentarily unchanged
during filling and then jumps
to the correct level
0 time
Measured value jumps
sporadically to 100 % dur-
ing filling
0 time
Measured value jumps to
≥ 100 % or 0 m distance
0
time
Measurement error during emptying
Fault description
Measured value remains
unchanged in the close
range during emptying
0 time
Measured value remains re-
producible in one position
during emptying
0
time
62
Cause
Echo from the probe end larger than the
product echo, for example, with products
with ε < 2.5 oil-based, solvents, etc.
r
Turbulence on the product surface, quick
filling
Changing condensation or contamina-
tion on the probe
Level echo is no longer detected in the
close range due to false signals in the
close range. The sensor goes into over-
fill protection mode. The max. level (0 m
distance) as well as the status message
"Overfill protection" are output.
Cause
False signal larger than the level echo
Level echo too small
Stored false signals in this position are
larger than the level echo
SITRANS LG270 - Operating Instructions
Rectification
Check parameter "Medium" and "Vessel
height", adapt if necessary
Check parameters, change if necessary,
e.g. in dosing vessel, reactor
Carry out a false signal suppression
Eliminate false signals in the close range
Check installation conditions
If possible, switch off the function "Over-
fill protection"
Rectification
Eliminate false signals in the close range
Remove contamination on the probe. Af-
ter having removed the source of the
false signals, the false signal suppres-
sion must be deleted.
Carry out a new false signal suppression
Delete false signal suppression
Carry out a new false signal suppression
PBD-51041506