Pepperl+Fuchs HiC5863, Руководство пользователя

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Functional Safety K*D0-RSH-1.1E.1, HiC5863(Y1)
List of Abbreviations
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7 List of Abbreviations
ESD E mergency S hut d own
FIT F ailure I n T ime in 10
-9
1/h
FMEDA F ailure M ode, E ffects, and D iagnostics A nalysis

s
Probability of safe failure

dd
Probability of dangerous detected failure

du
Probability of dangerous undetected failure

no effect
Probability of failures of components in the safety loop that have
no effect on the safety function.

not part
Probability of failure of components that are not in the safety loop

total (safety function)
Probability of failure of components that are in the safety loop
HFT H ardware F ault T olerance
MTBF M ean T ime B etween F ailures
MTTR M ean T ime T o R estoration
PCS P rocess C ontrol S ystem
PFD
avg
Average P robability of dangerous F ailure on D emand
PFH Average frequency of dangerous failure per hour
PLC P rogrammable L ogic C ontroller
PTC P roof T est C overage
SC S ystematic C apability
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
1
Proof Test Interval
B
10d
Number of switching cycles until 10 % of the components fail
dangerously
DC D iagnostic C overage of dangerous faults
MTTF
d
M ean T ime T o dangerous F ailure
PL P erformance L evel
SILCL SIL C laim L imit (for a subsystem)
DPS D ual P ole S witching
DTS D e-energized T o S afe function
ETS E nergized T o S afe function