Characteristic Safety Values - Pepperl+Fuchs SIL M-LB-4000-System Manual

Functional Safety M-LB-(Ex-)4000-System
Planning
3.4

Characteristic Safety Values

M-LB-4224, M-LB-4244, M-LB-4254
Parameters
Assessment type
Device type
Mode of operation
Safety function
2
SIL
Analysis

sd

su

dd

du

no effect

no part

total (safety function)
5
MTBF
Table 3.2
1
The safe state of the surge protection barrier depend on the application.
2
The maximum safety integrity level of the safety loop in which the device might be used depends on the
performance values of the whole safety loop or the elements of the safety loop. See application examples section.
3
Analysis 1 represents a worst case analysis.
4
Analysis 2 represents an analysis with the assumption that lead short circuits and short circuits to ground
are detectable or do not have an effect.
5
acc. to SN29500. This value includes failures which are not part of the safety function/MTTR = 24 h.
14
Characteristic values
Full assessment
A
Low demand mode or high demand mode
1
Pass through the signal
3
Analysis 1
0 FIT
3 FIT
0 FIT
10 FIT
37 FIT
1 FIT
13 FIT
2269 years
3
Analysis 2
0 FIT
3 FIT
7 FIT
3 FIT
37 FIT
1 FIT
13 FIT
2269 years
4