MEDC LD15 UL, Техническое руководство

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© MEDC 2018
01/18
Safety Function:
LD15 AC Beacon
Summary of Clauses
2/7.4.2 and 2/7.4.4
LD15 LED Beacon
Single Mode (1oo1)
LD15 LED Beacon
Redundant Mode (1oo2)
Verdict
Architectural constraints
Safe Failure Fraction (SFF)
HFT=0 HFT=1 Type B
67% 67%
SIL 1 (1oo1)
SIL 2 (1oo2)
Random hardware
failures: [h
-1
]
DD
DU
6.45E-09
6.247E-08
6.45E-10
6.247E-09
Random hardware
failures: [h
-1
]
SD
SU
0.00E+00
1.21E-07
0.00E+00
1.21E-08
Diagnostic coverage (DC) 0.00% 0.00%
PFD @ PTI = 8760Hrs, MTTR = 8 Hrs
2.74E-04 2.742E-05 SIL 3 (1oo1)
Average freq. of dangerous failure
(high demand-PFH)[h
-1
]
6.247E-08 6.247E-09 SIL 4 (1oo1)
Hardware safety integrity compliance Route 1
H
Systematic safety integrity compliance Route 1
S
Systematic Capability
(SC1, SC2, SC3, SC4)
SC2
Hardware safety integrity achieved
Limited to: SIL 1 (1oo1) & SIL 2 (1oo2) due to SFF value.
Assessment of Functional Safety - LD15 AC
This Beacon is intended for use in a safety system conforming to the requirements of IEC61508.
UL has conducted a Failure Modes Effect and Diagnostic Analysis (FMEDA) of the LD15 LED Beacon against the
requirements of IEC 61508-2 using a Proof Test interval of 8760hrs.
The results are shown below and are based on Route 1H.
The Beacon is classed as a Type B device.