Rockwell Automation Allen-Bradley AADvance T9110, Руководство по решениям

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66 Rockwell Automation Publication ICSTT-RM447M-EN-P - July 2019
Chapter 4 AADvance System Architectures
Analogue Output
For Analogue Output the following applies:
• The fail-safe state current of the analogue output module is less than 2
mA.
• A safe state is an output configured to go to a specific value, or
configured to hold last state. If the required safe state is larger than 4
mA, you must use dual analogue output modules for
High Demand
applications.
Table 7 - Modules for SIL 2 Fault Tolerant Output Architecture
SIL 2 Fault Tolerant Input and SIL 2 High Demand Architecture
A SIL 2 fault tolerant "High Demand" architecture has dual input, dual
processor and dual output modules. In a dual arrangement the input modules
operate in 1oo2D under no fault conditions, degrade to 1oo1D on the
detection of the first fault in either module, and will fail-safe when there are
faults on both modules.
A triple input module arrangement can also be configured if it is required to
increase the fault tolerance of the input. When a triple input module
arrangement is configured the input modules operate in a 2oo3D under no
fault conditions, degrade to 1oo2D on detection of the first fault in any
module, then degrade to 1oo1D on the detection of faults in any two modules,
and will fail-safe when there are faults on all three modules.
The processor will operate 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. For high demand applications the
processor must be repaired within the MTTR assumed in the PFD calculations
or the high demand safety instrumented functions must be shut down.
Position Module Type
I/P A & B 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 Base Unit
CPU A 2 x T9110 Processor Module, T9100 Processor Base Unit
O/P A T9451 Digital Output Module, 24 Vdc, 8 C T9851 Digital Output TA, 24 Vdc, 8 Channel,
Dual and T9300 I/O Base Unit or
1 x T9481/T9842 Analogue Output Module, 3/8 Channel, Is
T9881 Analogue Output TA, 8 Ch, Simplex
WARNING: For High Demand applications you must use a minimum of a
dual processor configuration. High demand energize to action applications
will require dual output modules. (Analogue Output Modules where the
normal output current is less than 4 mA are classed as energize to action
applications).