Characteristic Safety Values - Pepperl+Fuchs KFD2-SCD2-Ex LK Series Manual

Functional Safety KFD2-SCD2-Ex*.LK, HiD2038
Planning
3.4

Characteristic Safety Values

Parameters
Assessment type
Device type
Mode of operation
HFT
1
SIL
SC
Safety function

s

dd

du

total (safety function)
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
PFD for T = 10 years
avg 1
PTC
Safety reaction time
3
Fault reaction time
Table 3.1
1
The statement for the SIL rating is based on SFF, HFT and the assumption that this device typically uses 10 % of the failure budget
for the safety loop.
2
acc. to SN29500. This value includes failures which are not part of the safety function/MTTR = 24 h.
3
Time between fault detection and fault reaction
The characteristic safety values like PFD, SFF, HFT and T
SIL report/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
3
Transfer of the analog signals
0 FIT
153 FIT
36.9 FIT
190 FIT
80 %
216 years
-8
3.69 x 10 1/h
-4
1.62 x 10
-4
3.23 x 10
-4
8.08 x 10
-3
1.62 x 10
100 %
< 20 ms
< 1000 ms
are taken from the
1
are related to each other.
1
).
1