Omron SYSMAC CJ1W-PRM21, Operation Manual

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Troubleshooting Using LED Indicators
Section 7-2
Note The table above assumes that the RUN and the PRM LED indicators are ON
and the ERH indicator is OFF. Otherwise, refer to section 7-2-2 Unit Start-up
Errors , section 7-2-3 Unit Operational Errors or section 7-2-4 Unit Configura-
tion Errors .
Flashing/
Lit Not lit Not lit Not a valid combination.
Lit A Bus disturbance error has been detected.
This indicates a termination error (termina-
tion resistors are missing, or inductors are
not used), or two slave devices with the
same address.
• Switch the Unit to OFFLINE mode.
• Terminate the network at the appropriate
places (see section
2-4-2 Bus Termina-
tion).
• Check if any other faulty devices are on
the same network.
• Switch the Unit to CLEAR / OPERATE
mode again.
Flashing • None of the allocated slave stations
responds to the Master’s request mes-
sages.
• None of the slaves is in Data_Exchange
with the Master Unit.
This may indicate a loose network connec-
tor on the Master, or a broken cable.
• Switch the Unit to OFFLINE mode.
• Check the network wiring.
• Check if any other faulty devices are on
the same network.
• Check if actual slave addresses match
the configured addresses.
• Check if the slave parameter settings are
correct. If necessary change them, and
download them again.
• Switch the Unit to CLEAR / OPERATE
mode again.
Lit Not-Lit There are no errors. The Unit is in CLEAR or OPERATE mode and exchanging data.
Lit Not a valid combination.
Flashing At least one slave station has responded to
the Master’s request messages and is not
in Data Exchange. There is also at least
one slave which has either
• not responded to the Master’s requests
messages, or
• been parameterized incorrectly.
• Switch the Unit to OFFLINE mode.
• Check the network wiring.
• Check if any other faulty devices are on
the same network.
• Check if the slave parameter settings are
correct. Re-download after correction.
• Switch the Unit to CLEAR / OPERATE
mode again.
BST COMM BF Probable cause Correction