Expansion Module Fault Output - Allen-Bradley 1444-TSCX02-02RB User Manual

Configure Relays Chapter 7
Communication Fault
A communication fault is reported if a fault occurs with the Ethernet link from
the module.
Expansion Module Fault
An expansion module fault is reported if any of the connected expansion
modules report a module fault.
Each expansion module performs start-up tests of memory and function
similar to the main module.
The relay expansion module performs the relay drive test on its relays when
commanded by the main module.
Expansion Bus Fault
A timeout function is implemented that requires that a "Heartbeat™" from
each expansion module is provided to help verify that each module is
communicating and that the bus is functioning.
If the heartbeat period times out, bus fault is reported in case communication
between the main and any of its expansion modules fails.

Expansion Module Fault Output

The following faults can be detected and acted on by any of the 1444 series
expansion relay module (1444-RELX00-04RB) relays.
Module Fault
The relay expansion module itself reports this fault.
Each expansion module performs start-up tests of memory and function
similar to the main module.
The relay expansion module performs the relay drive test on its relays when
commanded by the main module.
Rockwell Automation Publication 1444-UM001D-EN-P - June 2018 207