4 remove interferences – VEGA VEGAPULS 62 (≥ 2.0.0 - ≥ 4.0.0) 4 … 20 mA_HART - two-wire, approval according to LPR radio standard User Manual
Page 59
Code
Text mes-
sage
Cause
Rectification
M
505
No echo avai-
lable
l Level echo can no longer
be detected
l Clean the antenna
l Use a more suitable an-
tenna/sensor
l Remove possible false
echoes
l Optimize sensor position
and orientation
9
.4 Remove interferences
The first measures are:
l
Evaluation of fault messages via the indicating and adjustment
module
l
Checking the 4 … 20 mA signal
l
Treatment of measurement errors
Further comprehensive diagnosis possibilities are offered by a PC with
the software PACTware and suitable DTM.
In many case, the failure reasons can thus be determined and faults
rectified.
Connect a handmultimeter in the suitable measuring range according
to the wiring plan. The following table describes possible errors in the
current signal and helps to remove them:
Error
Cause
Rectification
4 … 20 mA signal
not stable
l Level fluctua-
tions
l Set damping according to the in-
strument via the indicating and
adjustment module or PACTware/
DTM
4 … 20 mA signal
missing
l Electrical con-
nection faulty
l Check connection according to
chapter "Connection steps" and if
necessary, correct according to
chapter "Wiring plan".
l Voltage supply
missing
l Check cables for breaks; repair if
necessary
l Operating vol-
tage too low or
load resis-
tance too high
l Check, adapt if necessary
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
Procedure for fault rec-
tification
Check the 4 … 20 mA
signal
VEGAPULS
62 • 4 … 20 mA/HART - two-wire, approval according to LPR radio standard
59
9 Diagnosis, Asset Management and service
41718
-EN
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