Rockwell Automation 440R MSR300 Modular Safety Control System - Manual (Page 11)

MSR300 Safety System Manual
Rockwell Automation
MSR300 Manual.doc Pg 11 of 85
the system is. SILs are correlated to the probability of failure of demand (PFD), which is
equivalent to the unavailability of a system at the time of a process demand.
IEC/EN 61508 is approximately equivalent to ANSI/ISA-S84.0: Application of Safety
Instrumented Systems for the Process Industries," Instrument Society of America
Standards and Practices, 1996.
IEC/EN 61508 SIL 3 summary for the MSR300 System:
Safety Integrity Level:
SIL 3
10 -4 ≤ PFD ≤ 10 -3 (whole safety function)
10 -8 h -1 ≤ PFH ≤ 10 -7 h -1
SIL – part of logic unit:
15%
PFD ≤ 0,15 x 10 -3
PFH ≤ 0,15 x 10 -7
Mode of operation:
low demand mode (Ú PFD)
High demand mode (Ú PFH)
Safety related subsystems:
Type B (use of programmable / complex
Components)
Hardware Fault Tolerance:
HFT = 1 (two channel system)
Safe Failure Fraction:
SFF = 90% to 99% (61508-2, table3)
Calculations for MSR300:
MSR310 Base Module MSR329 Muting Lamp Module
PFD
av
(T
1
)≈ 5,9E-10 *t PFD
av
(T
1
)≈ 6,92E-11 *t
PFH(T
1
)≈ 1,2E-09 [1/h] PFH(T
1
)≈ 1,38E-10 [1/h]
MSR320 Input Module MSR330 Output Module
1-Channel Wiring PFD
av
(T
1
)≈ 2,50E-09 *t
PFD
av
(T
1
)≈ 3,19E-11 *t PFH(T
1
)≈ 5,00E-09 [1/h] 1 contact
PFH(T
1
)≈ 6,39E-11 [1/h]
2-Channel Wiring PFD
av
(T
1
)≈ 5,00E-09 *t
PFD
av
(T
1
)≈ 1,19E-11 *t PFH(T
1
)≈ 1,00E-08 [1/h] 2 contacts
PFH(T
1
)≈ 2,39E-11 [1/h]
3-Channel Wiring PFD
av
(T
1
)≈ 7,50E-09 *t
PFD
av
(T
1
)≈ 1,43E-11 *t PFH(T
1
)≈ 1,50E-08 [1/h] 3 contacts
PFH(T
1
)≈ 2,86E-11 [1/h]
Standard configuration:
MSR300 System consisting of: 1 MSR310, 4 MSR320, 1 MSR330, 1 MSR329
(Each MSR320 configured for two single channel inputs)
PFD
avSystem
(T
1
)= 8,17E-09 *t T
1
(15% PFD
zul
) Test interval: 2,1 Years
PFH(T
1
)= 1,63E-08 [1/h]