Eaton DB3B Mode D'emploi page 15

DB3B Sounder
Safety Function of DB3B Sounder:
To provide a pre-described audible warning sound when required
Summary of Clauses
2/7.4.2 and 2/7.4.4
Architectural constraints
Safe Failure Fraction (SFF)
λ
Random hardware
λ
failures: [h- ]
1
λ
Random hardware
λ
failures: [h- ]
1
PFD @ PTI = 8760Hrs MTTR = 8 Hrs
Average freq. of dangerous failure (high
demand-PFH)[h- ]
1
Hardware safety integrity compliance
Systematic safety integrity compliance
Systematic Capability
(SC1, SC2, SC3, SC4)
Hardware safety integrity achieved
DB3B Sounder
Single Mode (1oo1)
HFT=0
65.9%
6.5E+09
DD
1.16E-07
DU
0.00E+00
SD
2.18E-07
SU
5.09E-04
1.16E-07
Route 1
H
Route 1
S
SC2
Limited to: SIL 1 (1oo1) & SIL 2 (1oo2) due to SFF value.
Sounder - dB3B
DB3B Sounder Verdict
Redundant Mode (1oo2)
HFT=1 Type B
65.9% SIL 1(1oo1)
SIL 2 (1oo2)
6.5E+10
1.16E-08
0.00E+00
2.18E-08
5.09E-05
SIL 3(1oo1)
1.16E-08 SIL 2(1 oo1)
TM264 July 2020 www.eaton.com
Sounder - DB3B
English
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