Rockwell Automation 1794 FLEX I/O System with ControlLogix for SIL2 User Manual
Page 49
Publication 1794-RM001G-EN-P - December 2011
Failure Estimates A-3
1794-IT8
Thermocouple Input Module
1,564,324
6.39E-07
2.41E-05
1794-OB16
16 Source Output Module
1,883,594
5.31E-07
1.98E-05
1794-OB16P
Protected Output Module
2,135,280
4.68E-07
1.73E-05
1794-OB8EP
Protected Output Module
2,389,669
(2)
4.18E-07
1.54E-05
1794-OE4
Analog Output Module
23,807,086
4.20E-08
1.48E-06
1794-OF4I
Isolated Analog Output Module
7,191,128
1.39E-07
4.96E-06
1794-OW8
Relay Output Module
14,766,876
6.77E-08
2.40E-06
1794-TB3
Terminal Base Units
21,128,346
(2)
4.73E-08
1.67E-06
1794-TB3G
Generic Terminal Base Units
27,320,800
3.66E-08
1.29E-06
1794-TB3GS
Generic Terminal Base Units
46,425,600
2.15E-08
7.58E-07
1794-TB3S
Terminal Base Unit
71,433,747
(2)
1.40E-08
4.92E-07
1794-TB3T
Temperature Terminal Base Units
73,096,226
(2)
1.37E-08
4.81E-07
1794-TB3TS
Temperature Terminal Base Units
75,763,399
(2)
1.32E-08
4.64E-07
1794-TBN
Terminal Base Units
75,716,615
1.32E-08
4.64E-07
1794-TBNF
Fused Terminal Base Units
4,812,320
(2)
2.08E-07
7.47E-06
1794-ACNR15XT
ControlNet Redundant Media Adapter
8,223,684
1.22E-07
4.33E-06
1794-AENTRXT
10/100Mb Ethernet Redundant Communication Adapter 1,268,070
7.89E-07
3.02E-05
1794-OB8EPXT
8 Protected Output Module
14,771,049
6.77E-08
2.40E-06
1794-IB16XT
16 Sink Input Module
35,587,189
2.81E-08
9.90E-07
1794-OB16PXT
16 Protected Output Module
26,709,401
3.74E-08
1.32E-06
1794-IB10XOB6XT
10 Input/6 Output Combo Module
22,202,487
4.50E-08
1.59E-06
1794-OW8XT
8 Relay Output Module
18,518,519
5.40E-08
1.91E-06
1794-IE4XOE2XT
4 Input/2 Output Analog Combo Module
11,800,802
8.47E-08
3.00E-06
1794-IE8XT
8 Input analog Module
14,041,000
7.12E-08
2.52E-06
1794-OE4XT
4 Output Analog Module
11,381,744
8.79E-08
3.12E-06
1794-IF2XOF2IXT
2 Input/2 Output Isolated Analog Combo Module
6,317,918
1.58E-07
5.66E-06
1794-IF4IXT
4 Isolated Input Analog Module
7,297,140
1.37E-07
4.89E-06
1794-IF4ICFXT
4 Isolated Input Analog Module
7,297,140
1.37E-07
4.89E-06
1794-OF4IXT
4 Isolated Output Analog Module
5,493,902
1.82E-07
6.52E-06
1794-IJ2XT
2 Ch. Frequency Counter Module
11,714,128
8.54E-08
3.03E-06
1794-IRT8XT
8 TC/RTD Input Analog Module
8,204,792
1.22E-07
4.34E-06
(1)
MTBF measured in hours.
(2)
Calculated using field-based values for components
(3)
λ
= Failure Rate = 1 / MTB
Table A.2 MTBF Field Data and Per Module PFD Estimates - T
1
= 2 years
Catalog Number:
Description:
(MTBF)
(1)
λ
(3)
Estimated
PFD 1oo2