Characteristic Safety Values - Pepperl+Fuchs KFD2-SR3-2.2S Manual

Functional Safety KFD2-SR3-(Ex)2.2S
Planning
3.4

Characteristic Safety Values

Parameters acc. to IEC 61508
Assessment type and documentation
Device type
Mode of operation
HFT
SIL (SC)
Safety function
1

s

dd

du
1

total (safety function)

not part
1
SFF
2
MTBF
PFH
PFD for T = 1 year
avg 1
PFD for T = 2 years
avg 1
PFD for T = 5 years
avg 1
PTC
Table 3.2
1
"No effect failures" and "Annunciation failures" are not influencing the safety function and are therefore not
included in the SFF and the safety values of the safety function.
2
acc. to SN29500. This value includes failures which are not part of the safety function/MTTR = 24 h. The
value is calculated for one safety function of the device.
The characteristic safety values like PFD, PFH, SFF, HFT and T
the FMEDA report. Observe that PFD and T
The function of the devices has to be checked within the proof test interval (T
12
Characteristic values
Full assessment
A
Low demand mode or high demand mode
0
2
Normal/inverted operation
145 FIT
4.1 FIT
73 FIT
222 FIT
77 FIT
67 %
270 years
-8
7.26 x 10 1/h
-4
3.18 x 10
-4
6.36 x 10
-3
1.59 x 10
100 %
are related to each other.
1
are taken from
1
).
1