Pepperl+Fuchs HiC282 Series, Руководство пользователя

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2
018-
12
14
Functional Safety KCD2-SR-(Ex)*(.LB)(.SP), HiC282*
Planning
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 and
documentation
Full assessment
Device type A
Mode of operation Low Demand Mode or High Demand Mode
HFT 0
SIL (SC) 2
Safety function 1 relay output for 1 channel 2 relay outputs for a
1-channel device

s
99 FIT 126 FIT

dd
18.2 FIT 47.5 FIT

du
40.3 FIT 11.1 FIT

total (safety function)
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.
158 FIT 184 FIT

not part
58 FIT 58 FIT
SFF
1
74.5 % 93.99 %
PTC 100 % 100 %
MTBF
2
2
acc. to SN29500. This value includes failures which are not part of the safety function/MTTR = 8 h. The value is calculated
for one safety function of the device.
366 years 310 years
PFH 4.03 x 10
-8
1/h 1.11 x 10
-8
1/h
PFD
avg
for T
proof
= 1 year 1.93 x 10
-4
5.34 x 10
-5
PFD
avg
for T
proof
= 2 years 3.85 x 10
-4
1.06 x 10
-4
PFD
avg
for T
proof
= 5 years 5.77 x 10
-4
1.59 x 10
-4
Reaction time
3
3
Time between fault detection and fault reaction
< 20 ms
Table 3.3