Rockwell Automation 1785-Lxxx Enhanced and Ethernet PLC-5 Programmable Controllers - Manual (Page 352)

Publication 1785-UM012D-EN-P - July 2005
F-4 Troubleshooting
Controller Communication Channel Troubleshooting
Indicator Color Channel Mode Description Probable Cause Recommended Action
A or B Green
(steady) Remote I/O Scanner Active Remote I/O link, all
adapter modules are
present and not faulted
Normal operation No action required
Remote I/O Adapter Communicating with
scanner
DH+ Controller is transmitting or
receiving on DH+ link
Green
(blinking
rapidly or
slowly) Remote I/O Scanner At least one adapter is
faulted or has failed
• Power off at
remote rack
• Cable broken
• Restore power to
the rack
• Repair cable
DH+ No other nodes on network
Red
(steady) Remote I/O Scanner
Remote I/O Adapter
DH+ Hardware fault Hardware error Turn power off, then on
Check that the software
configurations match the
hardware set-up
Replace the controller.
Red
(blinking
rapidly or
slowly) Remote I/O Scanner All adapters faulted • Cable not
connected or
broken
• Power off at
remote racks
• Repair cable
• Restore power to racks
DH+ Bad communication on DH+ Duplicate
node detected
Correct station address
Off Remote I/O Scanner
Remote I/O Adapter
DH+ Channel offline Channel is not
being used Place channel online
if needed