Rockwell Automation 1734-IE4S POINT Guard I/O Safety Modules User Manual User Manual
Page 183
Rockwell Automation Publication 1734-UM013J-EN-P - July 2014
183
Safety Data
Appendix D
Figure 62 - PFD vs. Proof Test Interval 1734-OB8S Series A
Mission Time for all modules is 20 years.
PFD
Proof Test Interval [years]
Cat. No.
Proof Test Interval
(Mission Time)
PFD
PFH
(1/hour)
Spurious Trip Rate (STR)
(2)
(2) Calculated based on ISA TR-84 method.
MTTF
spurious
(3)
(years)
(3) Mean Time to Failure (Spurious).
Year
Hour
1734-IB8S
Series A
1
8760
2.11E-06
5.10E-10
2.666E-06
42.78
2
17520
4.23E-06
5
43800
1.06E-05
10
87600
2.11E-05
20
175200
4.23E-05
1734-OB8S
Series A
1
8760
2.13E-06
5.14E-10
3.229E-06
35.33
2
17520
4.27E-06
5
43800
1.07E-05
10
87600
2.13E-05
20
175200
4.27E-05
1734-IE4S
Series A
1
8760
1.6E-07
3.7E-11
9.402E-07
121.42
2
17520
3.2E-07
5
43800
8.1E-07
10
87600
1.6E-06
3.8E-11
10
(1)
(1) This data is for dual channel mode of operation.
87600
2.4E-06
5.5E-11
20
175200
3.3E-06
3.9E-11