Allen-Bradley 1756-L61S ControlLogix 5561S, Reference Manual

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Rockwell Automation Publication 1756-RM093J-EN-P - April 2018 11
Chapter
1
Safety Integrity Level (SIL) Concept
SIL 3 Certification 1756 and 1768 GuardLogix® controller systems are type-approved and certified
for use in safety applications up to and including SIL CL3 according to
IEC 61508 and IEC 62061, safety applications up to and including Performance
Level PLe (Category 4) according to ISO 13849-1. SIL requirements are based
on the standards current at the time of certification.
In addition, the standard tasks within 1756 GuardLogix controllers can be used
either for standard applications or SIL 2 safety applications as described in the
Using ControlLogix® in SIL 2 Applications Reference Manual, publication
1756-RM001 . In either case, do not use SIL 2 or standard tasks and variables to
build up safety loops of a higher level. The safety task is the only task certified for
SIL 3 applications.
The standard task in 1768 Compact GuardLogix controllers may not be used for
SIL 2 safety applications.
RSLogix 5000® programming software is required to create programs for 1756
and 1768 GuardLogix controllers.
Topic Page
SIL 3 Certification 11
Functional Verification Tests 12
GuardLogix Architecture for SIL 3 Applications 13
GuardLogix System Components 14
GuardLogix Certifications 16
GuardLogix PFD and PFH Specifications 16
Safety Integrity Level (SIL) Compliance Distribution and Weight 17
System Reaction Time 18
Safety Task Period and Safety Task Watchdog 19
Contact Information if Device Failure Occurs 19