Allen-Bradley MicroLogix 1200 - Analog Expansion IO Diagnostics and Troubleshooting; Module Operation and Channel Operation; Power-Up Diagnostics

Publication 1762-UM001D-EN-P - March 2004
C-4 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 1200 and 1500 Programmable Controllers Instruction
Set Reference Manual, publication 1762-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.
Table C.2 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.