KROHNE OPTISOUND 3020C 2wire EN - Manual (Page 34)

7 Maintenance and fault rectification
7.1 Maintenance
When used as directed in normal operation, OPTISOUND
3020 C is completely maintenance-free.
7.2 Fault rectification
OPTISOUND 3020 C offers maximum reliability. Nevertheless
faults can occur during operation. These may be caused by the
following, e.g.:
l
Sensor
l
Process
l
Power supply
l
Signal processing.
The first measures to be taken are to check the output signal
and evaluate fault messages via the indicating/adjustment
module. The procedure is described below.
Connect a hand-held multimeter with a suitable measuring
range acc. to the wiring plan.
?
4 … 20 mA signal not stable
l level fluctuations
à
set integration time via the indicating/adjustment
module
?
4 … 20 mA signal missing
l incorrect connection to power supply
à
Check connection acc. to chapter "Connection proce-
dure" and correct, if necessary, acc. to chapter "Wiring
plans"
l no power supply
à
check cables for line break, repair, if necessary
l supply voltage too low or load resistance too high
à
check and adapt, if necessary
Causes of malfunction
Fault rectification
Checking the 4 … 20 mA sig-
nal
34 OPTISOUND 3020 C - 4 … 20 mA/HART
Maintenance and fault rectification
30507
-EN
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