Endress+Hauser Levelflex FMP55 HART - 12 Diagnostics and Troubleshooting; General Trouble Shooting; General Errors

Levelflex FMP55 HART Diagnostics and troubleshooting
Endress+Hauser 77
12 Diagnostics and troubleshooting
12.1 General trouble shooting
12.1.1 General errors
Error Possible cause Remedial action
Device does not respond. Supply voltage does not match the
value indicated on the nameplate.
Connect the correct voltage.
The polarity of the supply voltage is
wrong.
Correct the polarity.
The cables do not contact the
terminals properly.
Ensure electrical contact between the
cable and the terminal.
Values on the display
invisible
Contrast setting is too weak or too
strong.
• Increase contrast by pressing  and
 simultaneously.
• Decrease contrast by pressing  and
 simultaneously.
The plug of the display cable is not
connected correctly.
Connect the plug correctly.
Display is defective. Replace display.
"Communication error" is
indicated on the display when
starting the device or
connecting the display
Electromagnetic interference Check grounding of the device.
Broken display cable or display plug. Exchange display.
Output current < 3.6 mA Signal cable connection incorrect. Check connection.
Electronics is defective. Replace electronics.
HART communication does
not function.
Communication resistor missing or
incorrectly installed.
Install the communication resistor (
250 Ω) correctly →  35.
Commubox connected incorrectly. Connect Commubox correctly →  49.
Commubox not switched to HART
mode.
Set the selection switch of the
Commubox to the HART position.
CDI communication does not
work.
Wrong setting of the COM port on
the computer.
Check the setting of the COM port on
the computer and change it if necessary.
Device measures incorrectly. Parametrization error Check and adjust parameterization.