Vega VEGACAL 60 Series, Руководство по безопасности

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1 Functional safety
VEGACAL series 60 • Two-wire 4 … 20 mA/HART
35593-EN-181129
1 Functional safety
1.1 General information
This safety manual applies for measuring systems consisting of
the capacitive sensor VEGACAL series 60 in the version two-wire
4 … 20 mA/HART:
VEGACAL 62, 63, 64, 65, 66, 69
Valid hardware and software versions:
•
Serial number of the electronics > 14557661
•
Sensor software from Rev. 1.01
The measuring system can be used for level measurement of liquids
and solids that meets the special requirements of safety engineering.
Due to the service-proven reliability, implemention is possible in a sin-
gle channel architecture up to SIL2 and in a multi-channel, diversitary
redundant architecture up to SIL3.
The use of the measuring system in a multiple channel, homogene-
ous redundant architecture is excluded.
The SIL conformity is confirmed by the verification documents in the
appendix.
SIL Safety Integrity Level
HFT Hardware Fault Tolerance
SFF Safe Failure Fraction
PFD
avg
Average Probability of dangerous Failure on Demand
PFH Probability of a dangerous Failure per Hour
FMEDA Failure Mode, Effects and Diagnostics Analysis
λ
sd
Rate for safe detected failure
λ
su
Rate for safe undetected failure
λ
dd
Rate for dangerous detected failure
λ
du
Rate for dangerous undetected failure
DC
S
Diagnostic Coverage of safe failures; DC
S
= λ
sd
/(λ
sd
+λ
su
)
DC
D
Diagnostic Coverage of dangerous failures; DC
D
= λ
dd
/(λ
dd
+λ
du
)
FIT Failure In Time (1 FIT = 1 failure/10
9
h)
MTBF Mean Time Between Failure
MTTF Mean Time To Failure
MTTR Mean Time To Repair
Further abbreviations and terms are stated in IEC 61508-4.
•
IEC 61508
– Functional safety of electrical/electronic/programmable elec-
tronic safety-related systems
•
IEC 61511-1
Scope
Application area
SIL conformity
Abbreviations, terms
Relevant standards