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1 functional safety, 1 in general, 1functional safety – KROHNE OPTISWITCH 5xx0C 2wire SIL EN User Manual

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1

Functional safety

1

.1 In general

This safety manual applies to measuring systems consisting of the
vibrating level switch OPTISWITCH series 5000 with integrated
oscillator SWE60Z:

OPTISWITCH 5100 C, 5150 C, 5200 C, 5250 C

For instruments with enamelled fork, oscillator SWE60Z.E or SWE60Z.
E

1 is required.

The measuring system can be implemented for level detection (of
liquids) which meets the special requirements of safety technology.

This is possible up to SIL2 in a single channel architecture (1oo1D),
and up to SIL3 in a multiple channel, redundant architecture.

The SIL declaration of conformity can be downloaded from our
homepage in the Internet.

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.

Scope

Area of application

SIL conformity

Abbreviations, terms

OPTISWITCH series 5000 • - two-wire

3

1 Functional safety

32750

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EN

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