Rockwell Automation T8xxx Trusted Communications Interface - Manual (Page 45)

Trusted
TM
Communication Interface T8151B
Issue 21 Apr 10 PD-T8151B 45
5. Fault Finding and Maintenance
5.1. Fault Reporting
The Communication Interface provides a module fault alarm on its System Healthy LED, which
indicates a module shutdown. No diagnostics are available via the module’s I/O complex equipment
definition. Diagnostic variables are available for Modbus Master configurations as described in section
3.5. Detailed communications diagnostics are available via the command line interface diagnostics as
described in section 5.4.
5.2. Module Faults
The Communication Interface is a simplex module. There are triplicated voting circuits for interfacing to
the system inter-module bus, but the remaining architecture has no redundant circuits. The
Communication Interface is certified as non-interfering and fail-safe. On failure of the processing
circuits or on communications conditions that the module cannot cope with, the module will shut down.
Safety related communications requires two communication interfaces providing the same services on
separate data links.
5.3. Module Replacement
The Communication Interface cannot be hot-swapped. If the module has shut down or
communications through the module has stopped, the module should be removed from the chassis
and then re-inserted into the chassis. It will automatically restart and load its communications settings
online.
The module performs a warm-start on an application load, a configuration download and an online
update and will then operate with the latest communications configuration.