Diagnostics And Troubleshooting; General Trouble Shooting; General Errors - Endress+Hauser Levelflex FMP55 Operating Instructions Manual

Levelflex FMP55 HART
Endress+Hauser
12

Diagnostics and troubleshooting

12.1

General trouble shooting

12.1.1

General errors

Error
Device does not respond.
Values on the display
invisible
"Communication error" is
indicated on the display when
starting the device or
connecting the display
Output current < 3.6 mA
HART communication does
not function.
CDI communication does not
work.
Device measures incorrectly.
Possible cause
Supply voltage does not match the
value indicated on the nameplate.
The polarity of the supply voltage is
wrong.
The cables do not contact the
terminals properly.
Contrast setting is too weak or too
strong.
The plug of the display cable is not
connected correctly.
Display is defective.
Electromagnetic interference
Broken display cable or display plug.
Signal cable connection incorrect.
Electronics is defective.
Communication resistor missing or
incorrectly installed.
Commubox connected incorrectly.
Commubox not switched to HART
mode.
Wrong setting of the COM port on
the computer.
Parametrization error
Diagnostics and troubleshooting
Remedial action
Connect the correct voltage.
Correct the polarity.
Ensure electrical contact between the
cable and the terminal.
• Increase contrast by pressing  and
 simultaneously.
• Decrease contrast by pressing  and
 simultaneously.
Connect the plug correctly.
Replace display.
Check grounding of the device.
Exchange display.
Check connection.
Replace electronics.
Install the communication resistor (
250 Ω) correctly →  35.
Connect Commubox correctly →  49.
Set the selection switch of the
Commubox to the HART position.
Check the setting of the COM port on
the computer and change it if necessary.
Check and adjust parameterization.
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