Pepperl+Fuchs KCD2-SCD-Ex1.SP, Руководство пользователя

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Functional Safety KCD2-SCD-Ex1.ES(.SP), HiC2031ES
Planning
20
20
-0
4
13
3.4 Characteristic Safety Values
The characteristic safety values like PFD, SFF, HFT and T
1
are taken from
the SIL report/FMEDA report. Observe that PFD and T
1
are related to each other.
The function of the devices has to be checked within the proof test interval (T
1
).
Parameters Characteristic values
Assessment type Full assessment
Device type A
Mode of operation Low demand mode or high demand mode
HFT 0
SIL 3
SC 3
Safety function Transfer of the analog signals

s
1
1
"No effect failures" are not influencing the safety function and are therefore not included in SFF and in the failure rates of the safety
function.
0 FIT

dd
177 FIT

du
8.2 FIT

total (safety function)
1
185 FIT

not part
41.2 FIT
SFF
1
95.6 %
MTBF
2
2
acc. to SN29500. This value includes failures which are not part of the safety function/MTTR = 24 h.
154 years
PFH 8.20 x 10
-9
1/h
PFD
avg
for T
1
= 1 year 4.25 x 10
-5
PFD
avg
for T
1
= 2 years 7.78 x 10
-5
PFD
avg
for T
1
= 5 years 1.84 x 10
-4
PTC 99 %
Safety reaction time
Fault reaction time
3
3
Time between fault detection and fault reaction
< 20 ms
< 1000 ms
Table 3.1