Allen-Bradley CompactLogix 1769-L23E-QB1B Installation Instructions Manual page 41

I/O Status Indicators
DC Inputs DC Outputs
Digital Inputs Status Indicators
There is one status indicator for each digital input point of the CompactLogix packaged
controller. When an input is ON, the corresponding input light is on (amber).
Digital Outputs Status Indicators
There is one status indicator for each digital output point of the CompactLogix packaged
controller. When an output is ON, the corresponding output light is on (amber).
Analog I/O Status Indicator
The analog I/O have one status indicator - the OK status indicator. If the indicator is green, the
analog I/O have power, have passed internal diagnostics, and are communicating properly. If
analog I/O OK indicator is off, a fault is present.
High-speed Counter Status Indicators
The high-speed counters have 12 status indicators.
Indicator Status
0,1,2, and 3 Amber
A0, A1, B0, B1, Z0, Amber
and Z1
FUSE Red
OK Off
Flashing red, brief
Steady green
Flashing green
Steady red
Flashing red, continuous
Power Supply Status
CompactLogix L23E
Description
The corresponding output is ON.
The corresponding input is ON (amber).
An overcurrent condition is present.
No power to the HSC.
The HSC is testing itself (this usually occurs at start-up).
The HSC is operating normally.
The HSC is not in Run mode.
A fault has occurred.
A HSC configuration error exists.
Rockwell Automation Publication 1769-IN082C-EN-P - February 2013
CompactLogix Controller 41
Analog I/O HSC