Rockwell Automation AADvance Controller Safety Manual - Manual (Page 93)

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Document: 553630
ICSTT-RM446K-EN-P Issue: 10
_C
4-37
Language Selection
The AADvance Workbench offers many programming tools to develop
algorithms to meet the needs of virtually any real-time control application. The
configuration and programming languages approved for use in SIL3 safety
related application are shown in the table.
Safety Related
Function Block (FB)
Instruction List (IL)
Structured Text (ST)
Ladder Diagrams (LD)
Sequential Function Chart (SFC)
 Safety Related Languages. The AADvance controller supports a
comprehensive set of certified functions. The certified functions set
includes the most commonly used function. These tested functions may be
used freely in the development of an application. Further functions may be
used subject to completion of testing commensurate with the level used
for the commonly used function
IL and ST include program flow control functions; these functions shall
be used with caution to ensure that infinite loop or omitted logic conditions
do not result. Where these constructs are used, it is recommended that full
branch and data coverage tests be performed on these sections of program. It
is recommended that only Boolean conditions be used for these constructs to
ensure that a feasible set of tests can be applied.
Application programmer generated function blocks may be created
either on a project specific or library basis. Where these functions are to be
used for safety-related applications, they shall be subject to exhaustive testing,
commensurate with that used for the commonly used functions. Once the
function block has been subject to this level of testing it may be used as for
commonly used functions.
Testing of New or Previously Untested Functions
Each safety-related software block shall be 100% testable, such functions could
be:
 Burner flame supervision including temperature and air/gas pressure
monitoring
 Burner gas-to-air ratio control/supervision
 Parts or whole of the start-up sequence of a batch reactor