VEGA VEGAPULS 61 (≥ 2.0.0 - ≥ 4.0.0) 4 … 20 mA_HART four-wire Approval according to LPR radio standard User Manual
Page 58
Error
Cause
Rectification
Current signal
greater than 22 mA
or less than
3.6 mA
l Electronics
module in the
sensor defecti-
ve
l Exchange the instrument or send it
in for repair
The below tables show typical examples of application-relevant
measurement errors with liquids. The measurement errors are
differentiated according to the following:
l
Constant level
l
Filling
l
Emptying
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)
Treatment of measure-
ment errors with liquids
58
VEGAPULS
61 • Approval according to LPR radio standard
9 Diagnosis, Asset Management and service
41714
-EN
-120301