Rectify Faults - Siemens SITRANS LG250 Operating Instructions Manual

Reaction when malfunc-
tion occurs
Fault rectification
Check the 4 ... 20 mA
signal
66
Code Cause
Text mes-
sage
M504 – Hardware defect
Error on an
device inter-
face
M505 – Sensor does not detect an
echo during operation
no measured
value avail-
able
– Process component or
probe contaminated or
defective
M506 – Error during setup
Installation/
Setup error
M507 – Error during setup
– Error when carrying out a
Error in the
reset
instrument
settings – False signal suppression
faulty
10.4 Rectify faults
The operator of the system is responsible for taking suitable meas-
ures to rectify faults.
The first measures to be taken are to check the output signal as well
as to evaluate the error messages via the display and adjustment
module. Further comprehensive diagnostics can be carried out on a
PC with the software PACTware and the suitable DTM. In many cases,
the causes can be determined this way 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
4 ... 20 mA signal Level fluctuations
not stable
4 ... 20 mA signal Electrical connec-
missing tion faulty
Voltage supply
missing
Operating voltage
too low or load re-
sistance too high
SITRANS LG250 - Operating Instructions
Rectification
– Exchanging the electronics
– Send instrument for repair
– Check and correct instal-
lation and/or parameter
adjustment
– Clean or exchange process
component or probe
– Check and correct instal-
lation and/or parameter
adjustment
– Check probe length
– Carry out reset and repeat
setup
Rectification
Set damping according to the instru-
ment via the display and adjustment
module or PACTware/DTM
Check connection according to
chapter "Connection steps" and if
necessary, correct according to chap-
ter "Wiring plan"
Check cables for breaks; repair if nec-
essary
Check, adapt if necessary
PBD-51041388