Net a and net b status indicators, Indicators interpreted together, Indicator interpreted independently – Rockwell Automation 20-COMM-Q ControlNet Adapter User Manual
Page 195: Net a and net b status indicators -3
Troubleshooting
7-3
20-COMM-C/Q ControlNet Adapter User Manual
Publication 20COMM-UM003F-EN-P
NET A and NET B Status
Indicators
These red/green bicolor LEDs indicate the status for the ControlNet
Channel A and Channel B network connections as shown in the tables
below. Depending on the state of these LEDs, they should be interpreted
together or independently.
Indicators Interpreted Together
Indicator Interpreted Independently
Status
Cause
Corrective Actions
Both LEDs Off
A reset occurred or the adapter is not
powered.
Apply power to the drive (or adapter if mounted in a DPI External
Comms Kit) and network.
Both LEDs Steady
Red
A link interface failed.
• Check media for broken cables, loose connectors, missing
terminators, and so forth.
• Cycle power to the drive (or adapter if mounted in a DPI External
Comms Kit) or reset the adapter. If the problem persists, contact
Rockwell Technical Support.
LEDs Alternately
Flashing Red/Green
The adapter is in self-test mode.
No action required. The adapter will exit this mode when the self-test is
completed.
LEDs Alternately
Flashing Red/Off
There is a bad node configuration.
• Verify that all node addresses are unique.
• Check the adapter’s configuration.
• Check media for broken cables, loose connectors, missing
terminators, etc.
• Cycle power to the drive (or adapter if mounted in a DPI External
Comms Kit) or reset the adapter.
Status
Cause
Corrective Actions
One channel LED is
Steady Off.
That channel is disabled or not
supported.
Program the network for redundant media, if required.
One channel LED is
Flashing Red/Green.
There is an invalid link configuration for
that channel.
• Cycle power to the drive (or adapter if mounted in a DPI External
Comms Kit) or reset the adapter.
• Reset the controller.
• If the problem persists, contact Rockwell Technical Support.
One channel LED is
Flashing Red/Off.
The channel is not receiving network
activity.
Check media for broken cables, loose connectors, missing terminators,
and so forth.
One channel LED is
Flashing Green/Off.
A temporary channel error has
occurred, or the channel is in
listen-only mode.
Verify the controller is present on the network and working.
One channel LED is
Steady Green.
Normal operation for that channel.
No action required.