User Manual Owner manual

222 Rockwell Automation Publication 1715-UM001C-EN-P - March 2014
Chapter 6 1715 Redundant I/O System in SIL 2 Safety Applications
This handles all fault scenarios:
• If a controller fault, such as a watchdog fault occurs, the controller goes to
program mode, which causes the 1715 I/O to go to the Program Mode
states.
• If there is a system fault that causes a communications loss to the I/O
modules, then the 1715 I/O will go to the Fault Mode states.
• If there is a CRTL (Connection Reaction Time Limit) timeout in the
1715-AENTR adapter, then the 1715 output modules will go to the Fault
Mode states.
For the 1715-OB8DE, the configuration is found under the Fault/Program
Action tab.
For the 1715-OF8I, the configuration is found under the Fault/Program Action
tab.
Additional Resources
For more information on using 1715 I/O modules in SIL 2 applications, see the
following resources:
• Chapter 7, Using SIL 2 Add-On Instructions with 1715 Redundant I/O
Modules on page 223
• Appendix E, PFD and PFH Calculations for a SIL 2 System on page 289
• Appendix F, SIL 2 Applications Checklist on page 303
• ControlLogix Controllers in SIL 2 Applications, publication
1756-RM001