Appendix 1: Possibilities To Reveal Dangerous Undetected Faults During The Proof Test - turck IM35-11Ex-Hi/24VDC Bedienungsanleitung

Appendix 1: Possibilities to reveal dangerous undetected faults during the
proof test
According to section 7.4.3.2.2 f) of IEC 61508-2 proof tests shall be undertaken to reveal
dangerous faults which are undetected by diagnostic tests.
This means that it is necessary to specify how dangerous undetected faults which have been
noted during the FMEDA can be detected during proof testing.
Table 7 and Table 8 show a sensitivity analysis of the ten most critical dangerous undetected
faults and indicate how these faults can be detected during proof testing.
Appendix 1 shall be considered when writing the safety manual as it contains important safety
related information.
Table 7: Sensitivity Analysis of dangerous undetected faults of IM33-**(Ex)-Hi/24VDC
Component
T8
IC6
IC3
IC4
IC8
IC13
IC2
IC9
IC7
C23
exida.com
© GmbH
Stephan Aschenbrenner
more@turck.com • www.turck.com • 2015/04
Anhang – EXIDA-Report FMEDA Turck 04/07-14 R001
% of total λ λ λ λ Detection through
du
100% functional test with monitoring of the
24,11%
expected output signal
100% functional test with monitoring of the
8,44%
expected output signal
100% functional test with monitoring of the
4,82%
expected output signal
100% functional test with monitoring of the
4,82%
expected output signal
100% functional test with monitoring of the
4,82%
expected output signal
100% functional test with monitoring of the
4,82%
expected output signal
100% functional test with monitoring of the
4,34%
expected output signal
100% functional test with monitoring of the
2,89%
expected output signal
100% functional test with monitoring of the
2,89%
expected output signal
100% functional test with monitoring of the
2,41%
expected output signal
TURCK 04-07-14 R001 V2R0.doc; February 8, 2013
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