Eaton Power Xpert C445 Safety Manual page 24

Safety Figures
All failure rate data in tables below are in FPMH
N ote:
(Failures per million hours)
Symbol
Safety Integrity Level SIL
Hardware Fault Tolerance HFT
Failure rate for detected
safe failures ʎ
SD
Failure rate for
undetected safe failures ʎ
SU
Failure rate for detected
dangerous failures
ʎ
DD
Failure rate for undetect-
ed dangerous failures ʎ
DU
Safe Failure Fraction SFF
Mean Time Before Failure MTBF
Average probability of
failure on demand PFD
Architecture
Lifetime
Proof Test Interval
Systematic capability
18 Safety Manual MN042004EN March 2017 www.eaton.com
C445BD-XALM
C445BD-XANM
C445BD-XALN
C445BD-XANN
1
0
(1) 0.229285
(2) 1.326801
(3) 0.000423
(4) 0.751464
68.4%
198683
7.519 X 10
-07
AVG
1oo1
20 Yrs
1 Yr
1
C445BD-XDLM C445BA-XDLM
C445BD-XDNM C445BA-XDNM
C445BD-XDLN C445BA-XDLN
C445BD-XDNN
1 1
0 0
0.364605 0.276269
1.394441 1.597322
0.000426 0.000426
0.770906 0.770906
69.5% 70.9%
192269 187112
7.713 X 10 7.713 X 10
-07
1oo1 1oo1
20 Yrs 20 Yrs
1 Yr 1 Yr
1 1
C445BA-XANM
C445BA-XALN
1
0
0.210949
1.529682
0.000426
0.751464
69.9%
193181
7.519 X 10
-07 -07
1oo1
20 Yrs
1 Yr
1