Rockwell Automation T71xx Regent+Plus Processor Modules 110 VAC, 220/240VAC and 24VDC - Manual (Page 2)

Processor Modules (T7110, 11, 12, 20, 21, and 22)
2 (Issue 1) I n d u s t r i a l
C o n t r o l S e r v i c e s
annunciated by an LED on the front of the processor module. In
addition, redundant fault contacts are activated to signal an
external device to alert operators to any permanent fault.
Module Operation
A block diagram of a typical processor module is shown in Figure
1.
Inside each processor module is a main processor, an I/O proc-
essor, and a power supply. A battery inside each of the processor
module maintains user application programs and the downloadable
portions of the system's RAMcode if there is a power failure. Each
processor module has interfaces to the processor Safetybus and the
I/O Safetybus. These interfaces consist of an input voter,
discrepancy detector logic, and an output driver.
Figure 1. Block Diagram of a Processor Module.
The voting and fault detection circuits allow the processor modules
to identify and isolate transient, intermittent, and permanent faults
as they occur. All faults are recorded in the system's fault history.
Each processor module contains its own power supply that
converts input power to the logic power levels used by the internal
processor circuits. The failure of one power supply will only effect