VEGA VEGAFLEX 86 4 … 20 mA_HART two-wire Rod and cable probe With SIL qualification - Manual (Page 73)

73
10 Diagnostics and service
VEGAFLEX 86 • 4 … 20 mA/HART two-wire
44234-EN-130823
Code
Text mes-
sage
Cause Rectification
M503
Reliability too
low
– The echot/noise ratio is the
small for a reliable meas-
urement
– Check installation and
process conditions
– Clean the antenna
– Change polarisation direc-
tion
– Use instrument with higher
sensitivity
M504
Error on an
device inter-
face
– Hardware defect – Check connections
– Exchanging the electronics
– Send instrument for repair
M505
No echo avail-
able
– Level echo can no longer
be detected
– Clean the antenna
– Use a more suitable
antenna/sensor
– Remove possible false
echoes
– Optimize sensor position
and orientation
10.4 Rectify faults
The operator of the system is responsible for taking suitable meas-
ures to rectify faults.
The first measures are:
•
Evaluation of fault messages, for example via the display and
adjustment module
•
Checking the output signal
•
Treatment of measurement errors
Further comprehensive diagnostics options offer a PC with the soft-
ware PACTware and the suitable DTM. In many cases, the reasons
can be determined in this way and faults can be rectified.
Connect a multimeter 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
– Fluctuations of
the measured
variable
– Set damping according to the
instrument via the display and
adjustment module or PACTware/
DTM
Reaction when malfunc-
tions occur
Procedure for fault recti-
fication
Check the 4 … 20 mA
signal