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Troubleshooting
Communication Channel
5-4
Enhanced, Ethernet,
and ControlNet PLC-5
processors only
troubleshooting – Enhanced, Ethernet, and ControlNet PLC-5 processor communication channel continued...
Indicator
Color
Channel Mode
Description
Probable Cause
Recommended Action
A or B
(continued)
red
(steady)
RIO scanner
RIO adapter
DH+
hardware fault
hardware error
Turn power off, then on. Check
that the software configurations
match the hardware set-up.
Replace the processor.
red
(blinking
rapidly or
slowly)
RIO scanner
faulted adapters detected
• cable disconnected 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
RIO scanner
channel off-line
channel is not being used
Place channel online if needed
RIO adapter
DH+
A
A
B