Pepperl+Fuchs SIL KCD2-STC-1.SP, Руководство по безопасности

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Safety Manual SIL KCD2-STC-(Ex)1.HC(.SP), HiC2025HC
Abbreviations
5 Abbreviations
DCS D istributed C ontrol S ystem
ESD E mergency S hut d own
FIT F ailure I n T ime
FMEDA F ailure M ode, E ffects and D iagnostics A nalysis
λ
s
Probability of safe failure
λ
dd
Probability of dangerous detected failure
λ
du
Probability of dangerous undetected failure
λ
no effect
Probability of failures of components in the safety path that have
no effect on the safety function
λ
not part
Probability of failure of components that are not in the safety path
λ
total (safety function)
Safety function
HFT H ardware F ault T olerance
MTBF M ean T ime B etween F ailures
MTTR M ean T ime T o R epair
PFD
avg
Average P robability of F ailure on D emand
PFH P robability of dangerous F ailure per H our
PTC P roof T est C overage
SFF S afe F ailure F raction
SIF S afety I nstrumented F unction
SIL S afety I ntegrity L evel
SIS S afety I nstrumented S ystem
T
proof
Proof Test Interval