BERTHOLD TECHNOLOGIES sens Serie Betriebsanleitung Seite 117

Band 1
SENSseries LB 480 Füllstandsmessung
BERTHOLD TECHNOLOGIES GmbH & Co. KG
7.12.2 Begriffsdefinition
SIL Safety Integrity Level
HFT Hardware Fault Tolerance
SFF Safe Failure Fraction
PFD Average Probability of Dangerous Failure on Demand
AVG
PFH Average Probability of Dangerous Failure on Demand
FMEDA Failure Mode, Effects and Diagnostics Analysis
FIT Failure in Time (1 FIT = 1 failure/109h)
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sd Rate for safe detected failure
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su Rate for safe undetected failure
   
s s = sd + su
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dd Rate for dangerous detected failure
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du Rate for dangerous undetected failure
DC Diagnostic Coverage
T1 Proof Test Interval
MTBF Mean Time Between Failure
MTTR Mean Time To Repair
IBN Inbetriebnahme
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