Allen-Bradley AADvance T9110, Руководство по безопасности

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48 Rockwell Automation Publication ICSTT-RM446N-EN-P - April 2018
Chapter 3 AADvance System Architectures
Digital Output
For Digital Output Modules the following applies:
• For energize to action high demand applications you must use dual
digital output modules.
Analogue Output
For Analogue Output the Following applies:
• The fail-safe state current of the Analogue Output module is less than
2mA.
• For energize to action high demand applications you must use dual
analogue output modules.
Table 6 - Modules for SIL 2 Fault Tolerant Output Architecture
Fault Tolerant Input and 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 non-faulted conditions and will
degrade to 1oo1D on the first detected fault. For high demand applications,
unless compensating measures are defined in the Safety Requirements
Specification (SRS) and documented in operating procedures, the application
program must be designed to shut down safety instrumented functions if a
Position Module Type
I/P A T9401/2 Digital Input Module, 24V dc, 8/16 Channel.
+ 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 1 x T9110 Processor Module, T9100 Processor Base Unit and 9300 I/O Base Unit
O/P A 1 × T9451 Digital Output Module, 24V dc, 8 Channel
+ T9851 Digital Output TA, 24V dc, 8 Channel, Dual
or
1 x T9481/T9842 Analogue Output Module, 3/8 Ch, Isolated
+ T9881 Analogue Output TA, 8 Ch, Simplex