Rockwell Automation Allen-Bradley AADvance T9110, Solutions Handbook

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64 Rockwell Automation Publication ICSTT-RM447M-EN-P - July 2019
Chapter 4 AADvance System Architectures
Table 5 - Modules for SIL 2 Fail-Safe Architecture
SIL 2 Fault Tolerant Input Architectures
A SIL 2 fault tolerant input architecture can have dual or triple input modules
with a dual processor and single output modules. The illustration shows a dual
input arrangement where the dual input modules operate in 1oo2D under no
fault conditions, they degrade to 1oo1D on detection of the first fault in either
module of the redundant pair, and when a fault occurs on the second module
the controller fails-safe.
The processor operates in 1oo2D under no fault conditions, will degrade to
1oo1D on the first fault in either processor module and will fail-safe when
there are faults on both processor modules. The output module operates in
1oo1D under no fault conditions and fail-safe on the first detected fault.
When a triple input module arrangement is configured the group of input
modules operate in 2oo3D under no fault conditions, degrade to 1oo2D on
the detection of first fault in any module, then degrade to 1oo1D on the
detection of faults in any two modules and fail-safe when there are faults on all
three modules.
NOTE Simplex output modules used for energize to action applications can only be
used for low demand applications.
Position Module Type
I/P A T9401/2 Digital Input Module, 24 Vdc, 8/16 C
T9801 Digital Input TA, 16 Channel, Simplex. or
T9431/2 Analogue Input Module, 8/16 C
T9831 Analogue Input TA, 16 Channel, Simplex
T9300 I/O Base Unit
CPU A 2 x T9110 Processor Module, T9100 Processor Base Unit
O/P A T9451 Digital Output Module, 24 Vdc, 8 Channel, Is
T9851 Digital Output TA, 24 Vdc 8 Channel, Simplex
1 x T9481/T9842 Analogue Output Module, 3/8 Ch, Is T9881 Analogue Output TA, 8 Ch,
Simplex
NOTE Simplex output modules used for energize to action applications can only be
used for low demand applications.