Allen-Bradley 1794 - Page 52

Publication 1794-RM001G-EN-P - December 2011
A-6 Failure Estimates
1794-OE4 Analog Output Module 23,807,086 4.20E-08 2.96E-10
1794-OF4I Isolated Analog Output Module 7,191,128 1.39E-07 9.90E10
1794-OW8 Relay Output Module 14,766,876 6.77E-08 4.78E-10
1794-TB3 Terminal Base Units
21,128,346
(2)
4.73E-08 3.33E10
1794-TB3G Generic Terminal Base Units 27,320,800 3.66E-08 2.57E10
1794-TB3GS Generic Terminal Base Units 46,425,600 2.15E-08 1.51E10
1794-TB3S Terminal Base Unit
71,433,747
(2)
1.40E-08 9.82E11
1794-TB3T Temperature Terminal Base Units
73,096,226
(2)
1.37E-08 9.59E11
1794-TB3TS Temperature Terminal Base Units
75,763,399
(2)
1.32E-08 9.25E11
1794-TBN Terminal Base Units 75,716,615 1.32E-08 9.26E-11
1794-TBNF Fused Terminal Base Units
4,812,320
(2)
2.08E-07 1.49E09
1794-ACNR15XT ControlNet Redundant Media Adapter 8,223,684 1.22E-07 8.64E-10
1794-AENTRXT 10/100Mb Ethernet Redundant Communication Adapter
1,268,070
(2)
7.89E-07 6.05E-09
1794-OB8EPXT 8 Protected Output Module 14,771,049 6.77E-08 4.78E-10
1794-IB16XT 16 Sink Input Module 35,587,189 2.81E-08 1.97E-10
1794-OB16PXT 16 Protected Output Module 26,709,401 3.74E-08 2.63E-10
1794-IB10XOB6XT 10 Input/6 Output Combo Module 22,202,487 4.50E-08 3.17E-10
1794-OW8XT 8 Relay Output Module 18,518,519 5.40E-08 3.80E-10
1794-IE4XOE2XT 4 Input/2 Output Analog Combo Module 11,800,802 8.47E-08 5.99E-10
1794-IE8XT 8 Input analog Module 14,041,000 7.12E-08 5.03E-10
1794-OE4XT 4 Output Analog Module 11,381,744 8.79E-08 6.22E-10
1794-IF2XOF2IXT 2 Input/2 Output Isolated Analog Combo Module 6,317,918 1.58E-07 1.13E-09
1794-IF4IXT 4 Isolated Input Analog Module 7,297,140 1.37E-07 9.75E-10
1794-IF4ICFXT 4 Isolated Input Analog Module 7,297,140 1.37E-07 9.75E-10
1794-OF4IXT 4 Isolated Output Analog Module 5,493,902 1.82E-07 1.30E-09
1794-IJ2XT 2 Ch. Frequency Counter Module 11,714,128 8.54E-08 6.04E-10
(1)
MTBF measured in hours.
(2)
Calculated using field-based values for components
(3)
λ = Failure Rate = 1 / MTBF
Table A.4 MTBF Field Data and Per Module PFH Estimates - T
1
= 1 year
Catalog Number: Description:
(MTBF)
(1)
λ
(3)
Estimated
PFH 1oo2