Omron SYSMAC CS Series Operation Manual page 229

Troubleshooting Using LED Indicators
BST COMM BF
Flashing/ Not lit Not lit
Lit
Lit
Flashing • None of the allocated slave devices
Lit Not-Lit
Lit
Flashing At least one slave device has responded to
208
Probable cause
Not a valid combination.
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.
responds to the master's request mes-
sages.
• None of the slaves is in I/O data
exchange with the Master Unit.
This may indicate a loose network connec-
tor on the Master Unit, or a broken cable.
There are no errors. The Unit is in CLEAR or OPERATE mode and exchanging data.
Not a valid combination.
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.
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.
Correction
• 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.
• 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.
• 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 correc-
tion.
• Switch the Unit to CLEAR / OPERATE
mode again.
Section 7-2