Siemens SITRANS LR150 - Rectify Faults; Diagnosis, Fault Messages

Diagnostics and troubleshooting
12.3Diagnosis, fault messages
• Signal processing
Fault rectification
The first measures are:
• Evaluation of fault messages
• Checking the output signal
• Treatment of measurement errors
A smart device (smartphone/tablet) with the adjustment app or a PC/notebook
with the PDM and the suitable EDD offer you further comprehensive diagnostic
possibilities. In many cases, the causes can be determined in this way and the faults
eliminated.
Reaction after fault rectification
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.
12.3 Diagnosis, fault messages
4…20mA signal
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
eliminate them:
Error Cause Rectification
4…20mA signal not
stable
Fluctuating measured value Set damping
Electrical connection faulty Check connection, correct, if
necessary
Voltage supply missing Check cables for breaks; repair if
necessary
4…20mA signal missing
Operating voltage too low, load
resistance too high
Check, adapt if necessary
Current signal greater
than 22mA, less than
3.6mA
Transmitter electronics defective Replace device or send in for repair
depending on device version
12.4 Status messages according to NE107
The transmitter features self-monitoring and diagnostics according to NE107 and
VDI/VDE2650. In addition to the status messages in the following tables there are
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SITRANS LR150
Operating Instructions, 08/2020, A5E50352155