Understanding the comm led, Understanding the comm led -2 – Rockwell Automation 160 DEVICENET (DN1) MODULE FRN 1-2.XX User Manual
Page 57
Publication 0160-5.5 - September 1997
7-2
Troubleshooting
Understanding the COMM LED
The COMM LED provides status information on Communication
Module operations. The table below shows how to use the LED to
detect and correct common operation problems.
Important: When power up occurs, the COMM LED flashes green
for 1/4 second, red for 1/4 second and then goes blank while the
Communication Module finishes its initialization.
!
ATTENTION: Do not attempt to defeat or override
fault circuits. The cause of a fault indication must be
determined and corrected before attempting operation.
Failure to correct a drive or system malfunction may
result in personal injury and/or equipment damage due
to uncontrolled machine system operation.
Table 1: Understanding the COMM LED
Color
State
What It Means:
What To Do:
None
The Communication module is not receiving power from the
network.
Check DeviceNet power and cable connections and the
power connection on the DeviceNet terminal block.
Red
Solid
Diagnostics test failed on powerup/reset. Internal fault
exists.
Cycle power to the drive and network. If the fault still exists,
return the Communication Module for repair.
Red
Solid
Duplicate DeviceNet node address. Two nodes cannot have
the same address.
Reset DIP switches 1 through 6 using a valid address and
reset device.
OR
If DIP switches 7 and 8 are both set to ON, change the
value of P18 - [Nonvolatile MAC] to a valid address and
reset device.
Red
Solid
Invalid data rate.
Reset DIP switches 7 and 8 to a valid data rate and reset
device.
OR
If DIP switches 7 and 8 are both set to ON, change value of
P19 - [Nonvolatile Baud] to a valid baud rate and reset
device.
Red
Flashing
I/O connection timed out.
Reset DeviceNet master device.
Green
Solid
Normal operating state and device is allocated to a master. No action required.
Green
Flashing
Device is on-line but not allocated to a master.
Check DeviceNet master for correct Communication Module
configuration information (node address, input assembly,
and output assembly).