User manual

Publication 1763-UM001E-EN-P - March 2015
192 Troubleshooting Your System
Analog Expansion I/O
Diagnostics and
Troubleshooting
Module Operation and Channel Operation
The module performs operations at two levels:
• module level
• channel level
Module-level operations include functions such as power-up, configuration,
and communication with the controller.
Internal diagnostics are performed at both levels of operation. Both module
hardware and channel configuration error conditions are reported to the
controller. Channel over-range or under-range conditions are reported in the
module’s input data table. Module hardware errors are reported in the
controller’s I/O status file. Refer to the MicroLogix 1100 Programmable
Controllers Instruction Set Reference Manual, publication 1763-RM001 for
more information.
When a fault condition is detected, the analog outputs are reset to zero.
Power-up Diagnostics
At module power-up, a series of internal diagnostic tests are performed.
Module Status LED State Table
If module
status LED is
Indicated
condition
Corrective action
On Proper Operation No action required.
Off Module Fault Cycle power. If condition persists, replace the
module. Call your local distributor or
Allen-Bradley for assistance.