User Manual Owner manual
Rockwell Automation Publication 1715-UM001C-EN-P - March 2014 291
PFD and PFH Calculations for a SIL 2 System Appendix E
PFD Calculations with 10-hour MTTR
The PFD calculations in Table 61 are calculated for a 1-year proof test interval
(8760 hours) and are specific to1715 I/O components in ControlLogix systems.
De-energize-to-trip 1-year Proof Test Interval
Table 61 - 1-year PFD Calculations for 1715 I/O Components
Cat No.
61508 2000
(1)
Series
Firmware
Version
(2)
Description
Simplex Configuration Duplex Configuration
PFDdePFDePFDdePFDe
1715-AENTR x A 2.001 EtherNet adapter redundant module 1.21E-04 1.55E-04 4.65E-07 7.84E-07
1715-IB16D x A 2.001 16-channel digital input module 4.04E-06 6.31E-06 4.29E-07 4.48E-07
1715-IF16 x A 2.001 16-channel analog input module 4.04E-06 6.31E-01 4.29E-07 4.48E-07
1715-OB8DE x A 2.001 8-channel digital output module 1.52E-06 4.14E-05 3.03E-06 4.16E-07
1715-OF8I x A 2.001 8-channel analog output module 2.91E-06 1.53E-04 5.79E-06 3.62E-06
(1) Calculated MTBF and PFD by FMEA to 61508-2000.
(2) For the latest approved versions, see the Revision Release List available from the Product Certifications link at http://www.ab.com.
Table 62 - De-energize-to-trip 1-year Proof Test Interval
MTTR 10 Hours PTI 1.0 Years Simplex Configuration Duplex Configuration
Cat No.
Series
Firmware
Version
Description
MTBF
λs
λdu
λdd
SFF
tce'
HFT
PFHde
PFDde
STR
β
βd
tce'
tge'
HFT
PFHde
PFDde
Arch
STR
1715-
AENTR
A 2.001 EtherNet
adapter
dual
module
841,973
8.43E-07
9.82E-09
3.34E-07
97.74%
N/A
N/A
N/A
N/A
N/A
1.0%
1.0%
1.14E+02
7.94E+01
1
3.45E-09
4.65E-07
1oo2D
8.43E-08
1715-
IB16D
A 2.001 16-
channel
digital
input
module
3,535,791
2.06E-07
6.57E-10
7.60E-08
99.77%
4.76E+01
0
7.48E-10
4.04E-06
2.82E-07
1.0%
0.5%
2.03E+01
1.68E+01
1
4.77E-10
4.29E-07
1oo2D
2.06E-09
1715-
IF16
A 2.001 16-
channel
analog
input
module
3,535,791
2.06E-07
6.57E-10
7.60E-08
99.77%
4.76E+01
0
7.48E-10
4.04E-06
2.82E-07
1.0%
0.5%
2.03E+01
1.68E+01
1
4.77E-10
4.29E-07
1oo2D
2.06E-09
1715-
OB8DE
A 2.001 16-
channel
digital
output
module
9,677,085
7.94E-08
2.96E-10
2.36E-08
99.26%
6.42E+01
1
7.66E-10
1.52E-06
1.03E-07
1.0%
1.0%
N/A
N/A
1
1.53E-09
3.03E-06
2oo2
7.94E-10
1715-
OF8I
A 2.001 16-
channel
analog
output
module
5,446,179
1.34E-07
5.50E-10
4.96E-08
99.51%
5.80E+01
1
8.90E-10
2.91E-06
1.83E-07
1.0%
0.5%
N/A
N/A
1
1.78E-09
5.79E-06
2oo2
1.34E-09