7 - troubleshooting, Dcm status indicators, Troubleshooting using the fault led (red) – Rockwell Automation 1747-DCM,D17476.8 Direct Communication Module User Manual
Page 53: Troubleshooting

7
Chapter
7–1
Troubleshooting
This chapter shows you how to identify and correct errors that you may
encounter using LEDs. The topics include:
•
DCM status indicators
•
troubleshooting using the FAULT LED (red)
•
troubleshooting using the COMM LED (green)
Two LEDs indicate the status of the DCM.
Red
Green
DCM
COMM
FAULT
If LED is:
Cause:
Corrective action:
On
Internal Fault
Cycle power to the I/O chassis containing the DCM.
Replace DCM if red LED remains lit after powerup.
Blinking
Configuration Error
Check that the DIP switch settings are correct. Make sure
that I/O group and rack size settings are compatible.
➀
Also see that the setting for rack address is correct. Refer
to chapter 4, Module Configuration, for help with DIP
switches.
Off
Normal State
No action required.
➀
The DCM cannot cross logical rack boundaries. Therefore, as an example, configuring the module for 1/2
logical rack with starting group 6 will cause a configuration error.
DCM Status Indicators
Troubleshooting Using the
FAULT LED (Red)