Allen-Bradley E Series Installation Instructions Manual page 21

3. Apply power to the module and check module status.
Use the following flowchart as a guide.
Turn the chassis
power supply on.
Module
status
indicator
red?
Yes
Module performs a
power-on self-test
initialization.
INIT
Module
status
indicator
red?
Yes
INIT has failed, and the
module displays an
error message. Refer to
Troubleshoot section.
Replace the module.
ControlLogix ControlNet Interface Module 21
See the
No
Troubleshoot
section.
Modules are in a
OR
redundant control
chassis pair.
Initialization is
No
complete. The
status indicator
blinks green.
Channel A and B
indicators alternately
flash.
Module
status
displays
OK?
Yes
Module is functional
and operating.
OK
A#xx
Publication
WAIT
SRM
Channel A and B
indicators display the
network condition as
listed on page 28.
See the
No
Troubleshoot
section.
1756-IN604A-EN-P - February 2006