VEGA VEGAPULS 68 (≥ 2.0.0 - ≥ 4.0.0) 4 … 20 mA_HART - two-wire - Manual (Page 62)

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9 Diagnosis, Asset Management and service
VEGAPULS 68 • 4 … 20 mA/HART - two-wire
36535-EN-130205
Measurement error during emptying
Fault description Error pattern Cause Rectification
6th measured value re-
mains unchanged in
the close range during
emptying
Level
time 0
– False echo larger than the level
echo
– Level echo too small
– Remove false echoes in the
close range. Check: Antenna
must protrude out of the socket
– Remove contamination on the
antenna
– Minimize interfering installati-
ons in the close range by chan-
ging the polarization direction
– After removing the false
echoes, the false signal
suppression must be deleted.
Carry out a new false signal
suppression
7th measured value
jumps sporadically to-
wards 100 % during
emptying
Level
time 0
– Varying condensation or conta-
mination on the antenna
– Carry out false signal suppres-
sion or increase false signal
suppression in the close range
by editing
– With bulk solids use radar sen-
sor with purging air connection
or flexible antenna cover
8th measured va-
lue fluctuates around
10 … 20 %
Level
time 0
– Various echoes from an uneven
product surface, e.g. an extrac-
tion funnel
– Check application parameter
"Medium type" and adapt, if
necessary
– Optimize installation position
and sensor orientation
– Reflections from the product
surface via the vessel wall
(deflection)
Depending on the reason for the fault and the measures taken, the
steps described in chapter "Setup" must be carried out again or must
be checked for plausibility and completeness.
Should these measures not be successful, please call in urgent cases
the VEGA service hotline under the phone no. +49 1805 858550.
The hotline is also available outside the normal working hours on
seven days a week around the clock.
Since we offer this service worldwide, the support is in the English
language. The service itself is free of charge, the only costs involved
are the normal call charges.
9.5 Exchanging the electronics module
If the electronics module is defective, it can be replaced by the user.
In Ex applications only one instrument and one electronics module
with respective Ex approval may be used.
If there is no electronics module available on site, the electronics mo-
dule can be ordered through the agency serving you. The electronics
modules are adapted to the respective sensor and differ in signal
output or voltage supply.
The new electronics module must be loaded with the default settings
of the sensor. These are the options:
Reaction after fault recti-
fication
24 hour service hotline