AADvance Safety Manual - Tuv-fs.com

AADvance Safety ManualSIL2 Fault Tolerant Output ArchitectureA SIL2 fault tolerant output architecture has dual output modules with simplexprocessor and input modules. In de-energize to trip operation, the output modules operate in 2oo2D no faultconditions and degrade to 1oo1D on the detection of the first fault in eithermodule. They fail-safe when there are faults on both modules. In energize to action operation, the output modules operate in 1oo2D under nofault conditions, degrade to 1oo1D on the detection of the first fault in eithermodule, and they fail-safe when there are faults on both modules.The illustration shows a dual output arrangement where the processor and inputmodules operate in 1oo1D under no fault conditions and will fail-safe on the firstdetected fault.Table 4:Modules for SIL2 Fault Tolerant Output ArchitecturePositionModule TypeI/P A 9401/2 Digital Input Module, 24V dc, 8/16 Channel. +9801 Digital Input TA, 16 Channel, Simplex or9431/2 Analogue Input Module, 8/16 Channel +9831 Analogue Input TA, 16 Channel, SimplexCPU AO/P A andO/P B1 x 9110 Processor Module, 9100 Processor Base Unitand 9300 I/O Base Unit2 × 9451 Digital Output Module, 24V dc, 8 Channel +9852 Digital Output TA, 24V dc, 8 Channel, Dual4-4 Document number 553630 Issue 7: February 2010